1938 United States Senate election in Iowa

The 1938 United States Senate election in Iowa took place on November 8, 1938. Incumbent Democratic Senator Guy M. Gillette, who won a special election to complete the unexpired term of Richard Louis Murphy, won a full term in office by defeating Republican former Senator Lester J. Dickinson. Gillette and Dickinson had briefly served together in the final months of 1936.

Primary elections were held on June 6. Gillette overcame a primary challenge from U.S. Representative Otha Wearin, who was personally recruited by President Franklin D. Roosevelt given Gillette's opposition to New Deal programs. Dickinson defeated Representative Lloyd Thurston for the Republican nomination.

Candidates

 * Wilson G. Byerhoff
 * Guy M. Gillette, incumbent Senator since 1936
 * Joseph J. Meyers
 * Mrs. Ellsworth Richardson
 * Otha Wearin, U.S. Representative from Glenwood

Candidates

 * Lester J. Dickinson, former U.S. Senator (1931–37)
 * Lloyd Thurston, U.S. Representative from Osceola

Candidates

 * G.W. Bauseman (Prohibition)
 * George F. Buresh (Farmer-Labor)
 * Lester J. Dickinson, former U.S. Senator (1931–37) (Republican)
 * Guy M. Gillette, incumbent Senator since 1936 (Democratic)
 * Raymond E. Hanke (Progressive)