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Party Division


Note: Statistics listed below reflect party division immediately following the election, unless otherwise noted. The actual number of senators representing a particular party often changes during a Congress, due to the death or resignation of a senator, or as a consequence of a member changing parties.

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1st Congress (1789–1791)

Majority Party: Pro-Administration (18 seats)

Minority Party: Anti-Administration (8 seats)

Total Seats: 26

Note: Organized political parties developed in the U.S. in the 1790s, but political factions—from which organized parties evolved—began to appear almost immediately after establishment of the federal government. Those who supported the Washington administration were referred to as "pro-administration" and would eventually form the Federalist party, while those in opposition joined the emerging (Jeffersonian) Republican party.

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2nd Congress (1791–1793)

Majority Party: Pro-Administration (16 seats)

Minority Party: Anti-Administration (13 seats)

Vacant: 1 Total Seats: 30

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3rd Congress (1793–1795)

Majority Party: Pro-Administration (16 seats)

Minority Party: Anti-Administration (14 seats)

Total Seats: 30

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4th Congress (1795–1797)

Majority Party: Federalists (21 seats)

Minority Party: Republicans (11 seats)

Total Seats: 32

Note: The Republican Party that emerged in the 1790s is also referred to as the Jeffersonian-Republican Party or the Democratic-Republican Party, and should not be confused with the modern (GOP) Republican Party established in the 1850s.

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5th Congress (1797–1799)

Majority Party: Federalists (22 seats)

Minority Party: Republicans (10 seats)

Total Seats: 32

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6th Congress (1799–1801)

Majority Party: Federalists (22 seats)

Minority Party: Republicans (10 seats)

Total Seats: 32

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7th Congress (1801–1803)

Majority Party: Republicans (17 seats)

Minority Party: Federalists (15 seats)

Vacant: 2

Total Seats: 34

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8th Congress (1803–1805)

Majority Party: Republicans (25 seats)

Minority Party: Federalists (9 seats)

Total Seats: 34

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9th Congress (1805–1807)

Majority Party: Republicans (27 seats)

Minority Party: Federalists (7 seats)

Total Seats: 34

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10th Congress (1807–1809)

Majority Party: Republicans (28 seats)

Minority Party: Federalists (6 seats)

Total Seats: 34

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11th Congress (1809–1811)

Majority Party: Republicans (27 seats)

Minority Party: Federalists (7 seats)

Total Seats: 34

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12th Congress (1811–1813)

Majority Party: Republicans (30 seats)

Minority Party: Federalists (6 seats)

Total Seats: 36

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13th Congress (1813–1815)

Majority Party: Republicans (28 seats)

Minority Party: Federalists (8 seats)

Total Seats: 36

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14th Congress (1815–1817)

Majority Party: Republicans (26 seats)

Minority Party: Federalists (12 seats)

Total Seats: 38

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15th Congress (1817–1819)

Majority Party: Republicans (30 seats)

Minority Party: Federalists (12 seats)

Total Seats: 42

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16th Congress (1819–1821)

Majority Party: Republicans (37 seats)

Minority Party: Federalists (9 seats)

Total Seats: 46

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17th Congress (1821–1823)

Majority Party: Republicans (44 seats)

Minority Party: Federalists (4 seats)

Total Seats: 48

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18th Congress (1823–1825)

Majority Party: Jackson & Crawford Republicans (31)

Minority Party: Adams-Clay Republicans & Federalists (17)

Total Seats: 48

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19th Congress (1825–1827)

Majority Party: Jacksonians (26 seats)

Minority Party: Adams (22 seats)

Total Seats: 48

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20th Congress (1827–1829)

Majority Party: Jacksonians (27 seats)

Minority Party: Adams (21 seats)

Total Seats: 48

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21st Congress (1829–1831)

Majority Party: Jacksonians (25 seats)

Minority Party: Anti-Jacksons (23 seats)

Total Seats: 48

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22nd Congress (1831–1833)

Majority Party: Jacksonians (24 seats)

Minority Party: Anti-Jacksons (22 seats)

Other Parties: 2 Nullifiers

Total Seats: 48

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23rd Congress (1833–1835)

Majority Party: Anti-Jacksons (26 seats)

Minority Party: Jacksonians (20 seats)

Other Parties: 2 Nullifiers

Total Seats: 48

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24th Congress (1835–1837)

Majority Party: Jacksonians (26 seats)

Minority Party: Anti-Jacksons (24 seats)

Other Parties: 2 Nullifiers

Total Seats: 52

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25th Congress (1837–1839)

Majority Party: Democrats (35 seats)

Minority Party: Whigs (17 seats)

Total Seats: 52

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26th Congress (1839–1841)

Majority Party: Democrats (30 seats)

Minority Party: Whigs (22 seats)

Total Seats: 52

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27th Congress (1841–1843)

Majority Party: Whigs (29 seats)

Minority Party: Democrats (22 seats)

Vacant: 1

Total Seats: 52

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28th Congress (1843–1845)

Majority Party: Whigs (29 seats)

Minority Party: Democrats (23 seats)

Total Seats: 52

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29th Congress (1845–1847)

Majority Party: Democrats (34 seats)

Minority Party: Whigs (22 seats)

Vacant: 2 Total Seats: 58

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30th Congress (1847–1849)

Majority Party: Democrats (38 seats)

Minority Party: Whigs (21 seats)

Other Parties: 1 Independent Democrat

Total Seats: 60

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31st Congress (1849–1851)

Majority Party: Democrats (35 seats)

Minority Party: Whigs (25 seats)

Other Parties: 2 Free Soilers

Total Seats: 62

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32nd Congress (1851–1853)

Majority Party: Democrats (36 seats)

Minority Party: Whigs (23 seats)

Other Parties: 3 Free Soilers

Total Seats: 62

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33rd Congress (1853–1855)

Majority Party: Democrats (38 seats)

Minority Party: Whigs (22 seats)

Other Parties: 2 Free Soilers

Total Seats: 62

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34th Congress (1855–1857)

Majority Party: Democrats (39 seats)

Minority Party: Oppositions (21 seats)

Other Parties: 1 American (Know Nothing); 1 Republican

Total Seats: 62

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35th Congress (1857–1859)

Majority Party: Democrats (41 seats)

Minority Party: Republicans (20 seats)

Other Parties: 5 American (Know Nothings)

Total Seats: 66

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36th Congress (1859–1861)

Majority Party: Democrats (38 seats)

Minority Party: Republicans (26 seats)

Other Parties: 2 American (Know Nothings)

Total Seats: 66

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37th Congress (1861–1863)

Majority Party: Republicans (31 seats)

Minority Party: Democrats (15 seats)

Other Parties: 3 Unionists

Vacant: 1 Total Seats: 50

Note: The decrease in total number of seats is due to secession of Confederate states. As members left the Senate to join the Confederacy, or were expelled for supporting the rebellion, seats were declared vacant. To establish a quorum with fewer members, a lower total seat number was taken into account.

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38th Congress (1863–1865)

Majority Party: Republicans (33 seats)

Minority Party: Democrats (10 seats)

Other Parties: 5 Unconditional Unionists; 4 Unionists

Total Seats: 52

Note: The decrease in total number of seats is due to secession of Confederate states. As members left the Senate to join the Confederacy, or were expelled for supporting the rebellion, seats were declared vacant. To establish a quorum with fewer members, a lower total seat number was taken into account.

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39th Congress (1865–1867)

Majority Party: Republicans (39 seats)

Minority Party: Democrats (11 seats)

Other Parties: 3 Unconditional Unionists; 1 Unionist

Total Seats: 54

Note:  The decrease in total number of seats is due to secession of Confederate states. As members left the Senate to join the Confederacy, or were expelled for supporting the rebellion, seats were declared vacant. To establish a quorum with fewer members, a lower total seat number was taken into account.

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40th Congress (1867–1869)

Majority Party: Republicans (57 seats)

Minority Party: Democrats (9 seats)

Vacant: 2

Total Seats: 68

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41st Congress (1869-–1871)

Majority Party: Republicans (62 seats)

Minority Party: Democrats (12 seats)

Total Seats: 74

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42nd Congress (1871–1873)

Majority Party: Republicans (56 seats)

Minority Party: Democrats (17 seats)

Other Parties: 1 Liberal Republican

Total Seats: 74

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43rd Congress (1873–1875)

Majority Party: Republicans (47 seats)

Minority Party: Democrats (19 seats)

Other Parties: 7 Liberal Republicans

Vacant: 1

Total Seats: 74

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44th Congress (1875–1877)

Majority Party: Republicans (46 seats)

Minority Party: Democrats (28 seats)

Other Parties: 1 Independent Republican

Vacant: 1

Total Seats: 76

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45th Congress (1877–1879)

Majority Party: Republicans (40 seats)

Minority Party: Democrats (35 seats)

Other Parties: 1 Independent

Total Seats: 76

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46th Congress (1879–1881)

Majority Party: Democrats (42 seats)

Minority Party: Republicans (33 seats)

Other Parties: 1 Independent

Total Seats: 76

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47th Congress (1881–1883)

Majority Party: Republicans (37 seats)

Minority Party: Democrats (37 seats)

Other Parties: 1 Independent; 1 Readjuster

Total Seats: 76

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48th Congress (1883–1885)

Majority Party: Republicans (38 seats)

Minority Party: Democrats (36 seats)

Other Parties: 2 Readjusters

Total Seats: 76

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49th Congress (1885–1887)

Majority Party: Republicans (42 seats)

Minority Party: Democrats (34 seats)

Total Seats: 76

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50th Congress (1887–1889)

Majority Party: Republicans (39 seats)

Minority Party: Democrats (37 seats)

Total Seats: 76

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51st Congress (1889–1891)

Majority Party: Republicans (51 seats)

Minority Party: Democrats (37 seats)

Total Seats: 88

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52nd Congress (1891–1893)

Majority Party: Republicans (47 seats)

Minority Party: Democrats (39 seats)

Other Parties: 2 Populists

Total Seats: 88

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53rd Congress (1893–1895)

Majority Party: Democrats (44 seats)

Minority Party: Republicans (40 seats)

Other Parties: 3 Populists; 1 Silver

Total Seats: 88

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54th Congress (1895–1897)

Majority Party: Republicans (44 seats)

Minority Party: Democrats (40 seats)

Other Parties: 4 Populists; 2 Silvers

Total Seats: 90

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55th Congress (1897–1899)

Majority Party: Republicans (44 seats)

Minority Party: Democrats (34 seats)

Other Parties: 5 Populists; 5 Silver Republicans; 2 Silvers

Total Seats: 90

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56th Congress (1899–1901)

Majority Party: Republicans (53 seats)

Minority Party: Democrats (26 seats)

Other Parties: 5 Populists; 3 Silver Republicans; 2 Silvers

Vacant: 1

Total Seats: 90

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57th Congress (1901–1903)

Majority Party: Republicans (56 seats)

Minority Party: Democrats (32 seats)

Other Parties: 2 Populists

Total Seats: 90

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58th Congress (1903–1905)

Majority Party: Republicans (57 seats)

Minority Party: Democrats (33 seats)

Total Seats: 90

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59th Congress (1905–1907)

Majority Party: Republicans (58 seats)

Minority Party: Democrats (32 seats)

Total Seats: 90

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60th Congress (1907–1909)

Majority Party: Republicans (61 seats)

Minority Party: Democrats (31 seats)

Total Seats: 92

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61st Congress (1909–1911)

Majority Party: Republicans (60 seats)

Minority Party: Democrats (32 seats)

Total Seats: 92

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62nd Congress (1911–1913)

Majority Party: Republicans (52 seats)

Minority Party: Democrats (44 seats)

Total Seats: 96

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63rd Congress (1913–1915)

Majority Party: Democrats (51 seats)

Minority Party: Republicans (44 seats)

Other Parties: 1 Progressive

Total Seats: 96

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64th Congress (1915–1917)

Majority Party: Democrats (56 seats)

Minority Party: Republicans (40 seats)

Total Seats: 96

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65th Congress (1917–1919)

Majority Party: Democrats (54 seats)

Minority Party: Republicans (42 seats)

Total Seats: 96

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66th Congress (1919–1921)

Majority Party: Republicans (49 seats)

Minority Party: Democrats (47 seats)

Total Seats: 96

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67th Congress (1921–1923)

Majority Party: Republicans (59 seats)

Minority Party: Democrats (37 seats)

Total Seats: 96

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68th Congress (1923–1925)

Majority Party: Republicans (53 seats)

Minority Party: Democrats (42 seats)

Other Parties: 1 Farmer-Labor

Total Seats: 96

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69th Congress (1925–1927)

Majority Party: Republicans (54 seats)

Minority Party: Democrats (41 seats)

Other Parties: 1 Farmer-Labor

Total Seats: 96

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70th Congress (1927–1929)

Majority Party: Republicans (48 seats)

Minority Party: Democrats (46 seats)

Other Parties: 1 Farmer-Labor

Vacant: 1

Total Seats: 96

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71st Congress (1929–1931)

Majority Party: Republicans (56 seats)

Minority Party: Democrats (39 seats)

Other Parties: 1 Farmer-Labor

Total Seats: 96

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72nd Congress (1931–1933)

Majority Party: Republicans (48 seats)

Minority Party: Democrats (47 seats)

Other Parties: 1 Farmer-Labor

Total Seats: 96

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73rd Congress (1933–1935)

Majority Party: Democrats (59 seats)

Minority Party: Republicans (36 seats)

Other Parties: 1 Farmer-Labor

Total Seats: 96

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74th Congress (1935–1937)

Majority Party: Democrats (69 seats)

Minority Party: Republicans (25 seats)

Other Parties: 1 Farmer-Labor; 1 Progressive

Total Seats: 96

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75th Congress (1937–1939)

Majority Party: Democrats (76 seats)

Minority Party: Republicans (16 seats)

Other Parties: 2 Farmer-Labors; 1 Progressive; 1 Independent

Total Seats: 96

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76th Congress (1939–1941)

Majority Party: Democrats (69 seats)

Minority Party: Republicans (23 seats)

Other Parties: 2 Farmer-Labors; 1 Progressive; 1 Independent

Total Seats: 96

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77th Congress (1941–1943)

Majority Party: Democrats (66 seats)

Minority Party: Republicans (28 seats)

Other Parties: 1 Independent; 1 Progressive

Total Seats: 96

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78th Congress (1943–1945)

Majority Party: Democrats (57 seats)

Minority Party: Republicans (38 seats)

Other Parties: 1 Progressive

Total Seats: 96

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79th Congress (1945–1947)

Majority Party: Democrats (57 seats)

Minority Party: Republicans (38 seats)

Other Parties: 1 Progressive

Total Seats: 96

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80th Congress (1947–1949)

Majority Party: Republicans (51 seats)

Minority Party: Democrats (45 seats)

Total Seats: 96

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81st Congress (1949–1951)

Majority Party: Democrats (54 seats)

Minority Party: Republicans (42 seats)

Total Seats: 96

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82nd Congress (1951–1953)

Majority Party: Democrats (49 seats)

Minority Party: Republicans (47 seats)

Total Seats: 96

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83rd Congress (1953–1955)

Majority Party: Republicans (48 seats)

Minority Party: Democrats (47 seats)

Other Parties: 1 Independent

Total Seats: 96

Note:  See Senate Membership Changes During the 83rd Congress

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84th Congress (1955–1957)

Majority Party: Democrats (48 seats)

Minority Party: Republicans (47 seats)

Other Parties: 1 Independent

Total Seats: 96

Note: Strom Thurmond (SC) was an Independent Democrat during this Congress until his resignation on April 4, 1956. In November of that year he was elected as a Democrat to fill the vacancy created by his resignation. The Independent member listed above was Wayne Morse (OR), who changed from an Independent to a Democrat on February 17, 1955.

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85th Congress (1957–1959)

Majority Party: Democrats (49 seats)

Minority Party: Republicans (47 seats)

Total Seats: 96

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86th Congress (1959–1961)

Majority Party: Democrats (65 seats)

Minority Party: Republicans (35 seats)

Total Seats: 100

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87th Congress (1961–1963)

Majority Party: Democrats (64 seats)

Minority Party: Republicans (36 seats)

Total Seats: 100

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88th Congress (1963–1965)

Majority Party: Democrats (66 seats)

Minority Party: Republicans (34 seats)

Total Seats: 100

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89th Congress (1965–1967)

Majority Party: Democrats (68 seats)

Minority Party: Republicans (32 seats)

Total Seats: 100

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90th Congress (1967–1969)

Majority Party: Democrats (64 seats)

Minority Party: Republicans (36 seats)

Total Seats: 100

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91st Congress (1969–1971)

Majority Party: Democrats (57 seats)

Minority Party: Republicans (43 seats)

Total Seats: 100

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92nd Congress (1971–1973)

Majority Party: Democrats (54 seats)

Minority Party: Republicans (44 seats)

Other Parties: 1 Conservative (caucused with the Republicans); 1 Independent (caucused with the Democrats)

Total Seats: 100

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93rd Congress (1973–1975)

Majority Party: Democrats (56 seats)

Minority Party: Republicans (42 seats)

Other Parties: 1 Conservative (caucused with the Republicans); 1 Independent (caucused with the Democrats)

Total Seats: 100

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94th Congress (1975–1977)

Majority Party: Democrats (61 seats)

Minority Party: Republicans (37 seats)

Other Parties: 1 Conservative (caucused with the Republicans); 1 Independent (caucused with the Democrats)

Total Seats: 100

Note: Results of the New Hampshire election were contested and the seat remained vacant until August 8, 1975, when Norris Cotton (R) was appointed to fill the seat until a special election could be held. John Durkin (D) won that special election and was sworn in on September 18, 1975. The statistics noted here reflect the Senate’s party division following Durkin’s election.

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95th Congress (1977–1979)

Majority Party: Democrats (61 seats)

Minority Party: Republicans (38 seats)

Other Parties: 1 Independent (caucused with the Democrats)

Total Seats: 100

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96th Congress (1979–1981)

Majority Party: Democrats (58 seats)

Minority Party: Republicans (41 seats)

Other Parties: 1 Independent (caucused with the Democrats)

Total Seats: 100

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97th Congress (1981–1983)

Majority Party: Republicans (53 seats)

Minority Party: Democrats (46 seats)

Other Parties: 1 Independent (caucused with the Democrats)

Total Seats: 100

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98th Congress (1983–1985)

Majority Party: Republicans (55 seats)

Minority Party: Democrats (45 seats)

Total Seats: 100

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99th Congress (1985–1987)

Majority Party: Republicans (53 seats)

Minority Party: Democrats (47 seats)

Total Seats: 100

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100th Congress (1987–1989)

Majority Party: Democrats (55 seats)

Minority Party: Republicans (45 seats)

Total Seats: 100

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101st Congress (1989–1991)

Majority Party: Democrats (55 seats)

Minority Party: Republicans (45 seats)

Total Seats: 100

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102nd Congress (1991–1993)

Majority Party: Democrats (56 seats)

Minority Party: Republicans (44 seats)

Total Seats: 100

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103rd Congress (1993–1995)

Majority Party: Democrats (57 seats)

Minority Party: Republicans (43 seats)

Total Seats: 100

Note: Party division changed to 56 Democrats and 44 Republicans after the June 5, 1993 election of Kay B. Hutchison (R-TX).

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104th Congress (1995–1997)

Majority Party: Republicans (52 seats)

Minority Party: Democrats (48 seats)

Total Seats: 100

Note: Party ratio changed to 53 Republicans and 47 Democrats after Richard Shelby of Alabama switched from the Democratic to Republican Party on November 9, 1994. It changed again, to 54 Republicans and 46 Democrats, when Ben Nighthorse Campbell of Colorado switched from the Democratic to Republican Party on March 3, 1995. When Robert Packwood (R-OR) resigned on October 1, 1995, the Senate divided between 53 Republicans and 46 Democrats with one vacancy. Ron Wyden (D) returned the ratio to 53 Republicans and 47 Democrats when he was elected to fill the vacant Oregon seat.

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105th Congress (1997–1999)

Majority Party: Republicans (55 seats)

Minority Party: Democrats (45 seats)

Total Seats: 100

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106th Congress (1999–2001)

Majority Party: Republicans (55 seats)

Minority Party: Democrats (45 seats)

Total Seats: 100

Note: As the 106th Congress began, the division was 55 Republican seats and 45 Democratic seats, but this changed to 54-45-1 on July 13, 1999, when Senator Bob Smith of New Hampshire switched from the Republican Party to Independent status. On November 1, 1999, Smith announced his return to the Republican Party, making the division once more 55 Republicans and 45 Democrats. Following the death of Senator Paul Coverdell (R-GA) on July 18, 2000, the balance shifted again, to 54 Republicans and 46 Democrats, when the governor appointed Zell Miller, a Democrat, to fill the vacancy.

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107th Congress (2001–2003)

Majority Party (Jan 3–20, 2001): Democrats (50 seats)

Minority Party: Republicans (50 seats)

Total Seats: 100

________

Majority Party (Jan 20–June 6, 2001): Republicans (50 seats)

Minority Party: Democrats (50 seats)

Total Seats: 100

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Majority Party (June 6, 2001–November 12, 2002): Democrats (50 seats)

Minority Party: Republicans (49 seats)

Other Parties: 1 Independent (caucused with the Democrats)

Total Seats: 100

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Majority Party (November 12, 2002–January 3, 2003): Republicans (50 seats)

Minority Party: Democrats (48 seats)

Other Parties: 2

Total Seats: 100

Note: From January 3 to January 20, 2001, with the Senate divided evenly between the two parties, the Democrats held the majority due to the deciding vote of outgoing Democratic Vice President Al Gore. Senator Thomas A. Daschle served as majority leader at that time. Beginning on January 20, 2001, Republican Vice President Richard Cheney held the deciding vote, giving the majority to the Republicans. Senator Trent Lott resumed his position as majority leader on that date. On May 24, 2001, Senator James Jeffords of Vermont announced his switch from Republican to Independent status, effective June 6, 2001. Jeffords announced that he would caucus with the Democrats, giving the Democrats a one-seat advantage, changing control of the Senate from the Republicans back to the Democrats. Senator Thomas A. Daschle again became majority leader on June 6, 2001. Senator Paul D. Wellstone (D-MN) died on October 25, 2002, and Independent Dean Barkley was appointed to fill the vacancy. The November 5, 2002 election brought to office elected Senator James Talent (R-MO), replacing appointed Senator Jean Carnahan (D-MO), shifting balance once again to the Republicans—but no reorganization was completed at that time since the Senate was out of session.  

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108th Congress (2003–2005)

Majority Party: Republicans (51 seats)

Minority Party:  Democrats (48 seats)

Other Parties: Independent (1 seat) (caucused with the Democrats)

Total Seats: 100

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109th Congress (2005–2007)

Majority Party: Republicans (55 seats)

Minority Party:  Democrats (44 seats)

Other Parties: 1 Independent (caucused with the Democrats)

Total Seats: 100

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110th Congress (2007–2009)

Majority Party: Democrats (49 seats)

Minority Party:  Republicans (49 seats)

Other Parties: 1 Independent; 1 Independent Democrat (both caucused with the Democrats)

Total Seats: 100

Note: Senator Joseph Lieberman of Connecticut was reelected in 2006 as an independent candidate and became an Independent Democrat. Senator Bernard Sanders of Vermont was elected as an Independent.

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111th Congress (2009–2011)

Majority Party: Democrats (57 seats)

Minority Party:  Republicans (41 seats)

Other Parties: 1 Independent; 1 Independent Democrat (both caucused with the Democrats)

Total Seats: 100

Note: Senator Arlen Specter was reelected in 2004 as a  Republican, and became a Democrat on April 30, 2009. Senator Joseph Lieberman of Connecticut was reelected in 2006 as an independent candidate, and became an Independent Democrat. Senator Bernard Sanders of Vermont was elected in 2006 as an Independent.

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112th Congress (2011–2013)
Majority Party: Democrats (51 seats)
Minority Party:  Republicans (47 seats)
Other Parties: 1 Independent; 1 Independent Democrat (both caucused with the Democrats)
Total Seats: 100

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113th Congress (2013–2015)
Majority Party: Democrats (53 seats)
Minority Party:  Republicans (45 seats)
Other Parties: 2 Independents (both caucused with the Democrats)
Total Seats: 100
Note: Senator Frank Lautenberg (D-NJ) died on June 3, 2013. He was replaced by Jeffrey Chiesa (R-NJ) on June 6, 2013, making the party division 52 Democrats, 46 Republicans, and 2 Independents (who both caucused with the Democrats). On October 31, 2013, Cory Booker (D-NJ) replaced Chiesa, returning the party division to 53 Democrats, 45 Republicans, and 2 Independents (who both caucused with the Democrats).

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114th Congress (2015–2017)
Majority Party: Republicans (54 seats)
Minority Party: Democrats (44 seats)
Other Parties: 2 Independents (both caucused with the Democrats)
Total Seats: 100

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115th Congress (2017–2019)
Majority Party: Republicans (51 seats)
Minority Party: Democrats (47 seats)
Other Parties: 2 Independents (both caucused with the Democrats)
Total Seats: 100
Note: At the beginning of 115th Congress, there were 52 Republicans and 46 Democrats. Senator Jeff Sessions (R-AL) resigned on February 8, 2017, and was replaced by Luther Strange (R-AL). Doug Jones (D-AL) subsequently won the special election held on December 12, 2017, to replace Sessions and was sworn into office on January 3, 2018.

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116th Congress (2019–2021)
Majority Party: Republicans (53 seats)
Minority Party: Democrats (45 seats)
Other Parties: 2 Independents (both caucus with the Democrats)
Total Seats: 100

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117th Congress (2021–2023)
Majority Party: Democrats (48 seats)
Minority Party: Republicans (50 seats)
Other Parties: 2 Independents (all caucus with the Democrats)
Total Seats: 100

Note: From January 3, 2021, to January 20, 2021, party division stood at 51 Republicans, 46 Democrats, 2 Independents (who caucused with the Democrats), and 1 vacancy. Both Senate seats in Georgia were up for election in 2020—the Class 2 seat held by Senator David Perdue, and the Class 3 seat held by appointed senator Kelly Loeffler (special election). No candidate in either race won a majority (50%+) as required by Georgia State law, forcing run-off elections for both seats held on January 5, 2021. Senator Perdue's term expired on January 3, 2021, resulting in a vacancy until the winner of the run-off election was sworn in. Democrats Jon Ossoff and Raphael Warnock defeated Perdue and Loeffler, respectively, in the run-off elections and were sworn in on January 20, bringing the party division to 50 Republicans, 48 Democrats, and 2 Independents (who caucus with the Democrats). Democrats hold the majority due to the tie-breaking vote of Vice President Kamala Harris.

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118th Congress (2023–2025)
Majority Party: Democrats (48 seats)
Minority Party: Republicans (49 seats)
Other Parties: 3 Independents
Total Seats: 100

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Party Division in the House of Representatives

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