The 1964 United States Senate election in New Mexico took place on November 3, 1964. Incumbent Republican U.S. Senator Edwin L. Mechem, who appointed himself to the office after the death of his predecessor, sought election to a full term. However, he was defeated by Democrat Joseph Montoya. Mechem was an ally of Arizona Senator and candidate for president Barry Goldwater who lost in a landslide on the same ballot. This and his very conservative voting record were widely seen as reasons for his loss.
