Total: 17 (13 Democrats and 4 Republicans)

As of January 2009

Democrats
Boxer, Barbara -- CA
Cantwell, Maria -- WA
Feinstein, Dianne - CA

Gillibrand, Kirsten -- NY

Hagan, Kay -- NC
Klobuchar, Amy -- MN

Landrieu, Mary - LA
Lincoln, Blanche - AR

McCaskill, Claire -- MO
Mikulski, Barbara - MD
Murray, Patty - WA

Shaheen, Jeanne -- NH
Stabenow, Debbie -MI

Republicans
Collins, Susan - ME
Hutchinson, Kay Bailey - TX
Murkowski, Lisa -AK
Snowe, Olympia --ME