The 1972 United States Senate election in Iowa took place on November 7, 1972. Incumbent Republican U.S. Senator Jack Miller ran for re-election to a third term but was defeated by Democrat Dick Clark. Iowa was one of fifteen states alongside Alabama, Arkansas, Colorado, Delaware, Georgia, Louisiana, Maine, Minnesota, Mississippi, Montana, New Hampshire, Rhode Island, South Dakota and West Virginia that were won by Republican president Richard Nixon in 1972 that elected Democrats to the United States Senate.