The 1964 United States Senate election in Maine was held on November 3, 1964. Incumbent DemocratEdmund Muskie was re-elected to a second term in office over Republican U.S. Representative Clifford McIntire. This was the first senate race for this particular seat in which the election was held in November and not September. This was the first time since 1851 that an incumbent Democratic Senator from Maine was re-elected or won re-election.