The 1946 United States Senate election in Washington was held on November 5, 1946. Incumbent Democrat Hugh Mitchell, who had been appointed to fill the unexpired term of Monrad Wallgren, ran for a full term in office, but was defeated by Republican Mayor of Tacoma Harry Cain.

After this election, no Republican would be elected to either of Washington's U.S. Senate seats until 1980, when Slade Gorton defeated incumbent Warren Magnuson; while no Republican would win this Senate seat until 1983; when Daniel J. Evans defeated Mike Lowry in the special election after the death of Cain's successor, Henry M. Jackson.

Blanket primary Candidates Democratic Sam C. Herren Russell Fluent, Washington State Treasurer Hugh Mitchell, interim U.S. Senator since 1945

Republican Harry Cain, Mayor of Tacoma J. Parkhurst Douglass

Results

General election Results

See also 1946 United States Senate elections

References