Harold Edward Stassen (April 13, 1907 – March 4, 2001) was an American politician who was the 25th governor of Minnesota. He was a leading candidate for the Republican nomination for president of the United States in 1948, considered for a time to be the front-runner. He thereafter regularly continued to run for that and other offices, such that his name became most identified with his status as a perennial candidate.

Born in West St. Paul, Minnesota, Stassen was elected as the county attorney of Dakota County, Minnesota after graduating from the University of Minnesota. He won election as Governor of Minnesota in 1938. Stassen is the youngest person elected to that office. He gave the keynote address at the 1940 Republican National Convention. He resigned as governor to serve in the United States Navy during World War II, becoming an aide to Admiral William Halsey Jr. After the war, he became president of the University of Pennsylvania, holding that position from 1948 to 1953. Stassen sought the presidential nomination at the 1948 Republican National Convention, winning a significant share of the delegates on the first two ballots of the convention. During the Republican primaries preceding the convention, he engaged in the Dewey–Stassen debate, the first recorded debate between presidential candidates.

Stassen sought the presidential nomination again at the 1952 Republican National Convention, and helped Dwight D. Eisenhower win the nomination by shifting his support to Eisenhower. After serving in the Eisenhower administration, Stassen sought various offices. Between 1958 and 1990, he campaigned unsuccessfully for the positions of Governor of Pennsylvania, Mayor of Philadelphia, United States Senator, Governor of Minnesota, and United States Representative. He further sought the Republican nomination for president in 1964, 1968, 1976, 1980, 1984, 1988, and 1992.