The 1954 United States Senate elections was a midterm election in the first term of Dwight D. Eisenhower's presidency. The 32 Senate seats of Class 2 were contested in regular elections, and six special elections were held to fill vacancies. Eisenhower's Republican party lost a net of two seats to the Democratic opposition. This small change was just enough to give Democrats control of the chamber with the support of an Independent who agreed to caucus with them, he later officially joined the party in April 1955.

William Fife Knowland was an American politician and newspaper publisher. A member of the Republican Party, he served as a United States Senator from California from 1945 to 1959. He was Senate Majority Leader from August 1953 to January 1955 after the death of Robert A. Taft, and would be the last Republican Senate Majority Leader until Howard Baker in 1981.