Senate Majority Leader

The Senate majority leader appears nowhere in the Constitution or in statute. The Vice President is the Senate's constitutional presiding officer, but has little practical power, and for its first century the Senate had no formal leaders at all. Party caucuses began electing floor leaders in the early twentieth century, Democrats formally choosing Oscar Underwood in 1920 and Republicans Charles Curtis in 1925. The majority leader is elected by the majority party's senators at the start of each Congress.

The majority leader's main source of power is a precedent: the right of first recognition. Since the 1930s the presiding officer recognizes the majority leader before any other senator who seeks the floor, which lets the leader move to proceed to bills, offer amendments first, fill the amendment tree to block others, and file cloture. The leader negotiates the unanimous consent agreements that govern nearly all Senate business, schedules floor time for legislation and nominations, and serves as the party's chief spokesperson.

Because the filibuster requires sixty votes for most legislation, a majority leader must usually negotiate with the minority, which gives the office less raw power than the Speaker of the House. Lyndon Johnson, majority leader in the 1950s, is remembered as the most commanding, and Mitch McConnell, Republican leader from 2007 to 2025, was the longest-serving party leader in Senate history. McConnell used the office to block the 2016 Supreme Court nomination of Merrick Garland and to confirm hundreds of judges. John Thune became majority leader in January 2025.