Serving as Democratic whip when Senate Majority Leader Lyndon B. Johnson resigned in 1961 to become vice president, Mike Mansfield was a logical choice to succeed Johnson. He was reluctant to become floor leader, however, being a Catholic at a time when the nation had just elected its first Catholic president. President John F. Kennedy and Vice President Johnson convinced him to take the job, and Mansfield served a record-setting 16 years as majority leader. His style of leadership, which shared power widely among senators, facilitated enactment of a profusion of legislation in the 1960s and '70s. He was particularly instrumental in guiding the strategy that broke a filibuster and allowed for passage of the Civil Rights Act of 1964. In 1998, 21 years after leaving office, Mansfield returned to the Capitol to inaugurate the Leader's Lecture Series.