Harold Edward Stassen (April 13, 1907 - March 4, 2001) was the 25th Governor of Minnesota from 1939 to 1943. At 31, he was the youngest governor to serve in Minnesota and was seen as an "up and comer" after delivering the keynote address at the 1940 Republican National Convention. At that convention, he helped secure the GOP nomination for Wendell Wilkie.

He resigned from office in 1943 to join the United States Navy during World War II. He was a delegate at the San Francisco Conference that established the United Nations, and president of the University of Pennsylvania from 1948 to 1953.

He was best known for having been a perennial candidate for the Republican Party nomination for President, seeking it nine times between 1948 and 1992. However, he never won the nomination.

He also ran for:

• governor of Minnesota on four occasions (winning twice),
• governor of Pennsylvania twice,
• United States Senate twice, and
• mayor of Philadelphia once.

Stassen's strongest bid for the presidential nomination was in 1948 when he won a series of upset victories in early primaries. Polls showed that he would beat Harry S. Truman if nominated. He lost the nomination to Thomas Dewey, however.

Stassen played a key role in the 1952 Republican contest when he released his delegates to Dwight David Eisenhower. This helped Eisenhower to defeat Robert Taft on the first ballot.

He gained a reputation as a liberal, particularly when, as president of the American Baptist Convention in 1963, he joined Martin Luther King in his march on Washington, D.C..