(CNN) -- George Stanley McGovern, a staunch liberal who served South Dakota in the U.S. Senate and House for more than two decades and who ran unsuccessfully as the Democratic Party nominee for president in 1972, died Sunday at the age of 90, his family said.
"Our wonderful father, George McGovern, passed away peacefully at the Dougherty Hospice House in Sioux Falls, SD, surrounded by our family and life-long friends," his family said in a statement.
The son of a Wesley Methodist minister, McGovern was born in Avon, South Dakota, on July 19, 1922. Six years later, his family moved an hour north to Mitchell, where McGovern graduated from Mitchell High School in 1940.
His debating skills won him a scholarship to Dakota Wesleyan University in Mitchell, where he met fellow student Eleanor Stegeberg. Three years later, they married. All five of their children were born in Mitchell.
McGovern's political skills came to the fore in college, where he was twice elected class president and won the state oratorical contest on the topic "My Brother's Keeper," which laid out his liberal beliefs.
In 1942, he enlisted in the U.S. Army Air Corps and went on to fly 35 combat missions as a B-24 bomber pilot in Europe. He was awarded the Distinguished Flying Cross.
After the war, he returned to college, graduating in 1946. McGovern attended Garrett Seminary for a year before entering Northwestern University in Chicago, where he got his M.A. and Ph.D. degrees in American history and government.
He returned to Dakota Wesleyan University in 1950 as a professor of history and political science, leaving in 1955 to help the South Dakota Democratic Party and launch his political career.
In 1956, he won a seat in Congress and was re-elected two years later.
After losing a bid for the U.S. Senate in 1960, McGovern was named special assistant to the president and director of the Food for Peace Program by President John F. Kennedy.
Two years later, he was elected to the Senate and reelected in 1968 and 1974. He served on Senate committees on agriculture, nutrition, forestry and foreign relations, and the Joint Economic Committee.
In 1972, Senator McGovern was selected as the Democratic Party nominee for president on a platform that included ending the war in Vietnam at a time when the country was torn over U.S. involvement there.
"Let us resolve that never again will we send the precious young blood of this country to die trying to prop up a corrupt military dictatorship abroad," he said to applause at the Democratic convention in Miami Beach, Fla.
He called the unemployment of more than 5 million Americans "the most false and wasteful economics of all" and said his highest domestic priority would be "to ensure that every American able to work has a job to do." He called for an end to a system of economic controls "in which labor is depressed but prices and corporate profits run sky high," and he called for national health insurance and "a fair and just tax system."
But the campaign started out poorly. He selected as running mate Sen. Thomas Eagleton of Missouri after a background check that did not turn up the fact that Eagleton had been treated for mental illness, a fact that was revealed soon thereafter. Eagleton withdrew and McGovern then tapped Sargent Shriver, a brother-in-law of John F. Kennedy and U.S. ambassador to France.
The pair ended up losing in a lopsided vote for incumbent Richard Nixon, with the McGovern ticket earning only 17 electoral votes -- from Massachusetts and the District of Columbia -- to Nixon's 520.
McGovern reflected on that defeat in a September piece in The Washington Post, calling it "a significant personal setback" that left him "genuinely stunned."
"The loss is there, an old wound never fully healed. My disappointment was certainly personal, made deeper by the awareness that many thousands of young Americans, and far more Vietnamese and other Asian citizens, were going to and did lose their lives with the Nixon administration's continuation of the war," he wrote. "And I was upset that my supporters would carry the burden of the loss, too -- something that has weighed on me all these years."
But he added, "I am optimistic about the country, and I am convinced that McGovern for President 1972 helped put those ideals within sight and completion today."
He returned to the Senate, where he was re-elected in 1974. But he was beaten when he sought a fourth term in 1980, a victim of what became known as the Reagan Revolution that swept conservatives into power and their views into vogue.
Four years later, he tried again to win the Democratic presidential nomination, but dropped out and former Vice President Walter Mondale became the nominee -- only to lose to Reagan in another lopsided race.
After leaving the Senate, McGovern taught at a number of schools, including Columbia University, Northwestern University, Cornell University, American University and the University of Berlin. He served as the president of the Middle East Policy Council from 1991 to 1998. President Bill Clinton appointed him ambassador to the United Nations Food and Agriculture Organization in Rome and, in 2000, awarded him the Presidential Medal of Freedom.
In 2001, McGovern was named the first United Nations global ambassador on hunger.
In 2008, McGovern switched his allegiance from Hillary Clinton to Barack Obama. But in a 2009 commentary in the Post, he lashed out at the Obama administration its policies in Afghanistan and reflected on one of the hallmarks of his political life.
"As a U.S. senator during the 1960s, I agonized over the badly mistaken war in Vietnam," McGovern wrote. "After doing all I could to save our troops and the Vietnamese people from a senseless conflict, I finally took my case to the public in my presidential campaign in 1972. Speaking across the nation, I told audiences that the only upside of the tragedy in Vietnam was that its enormous cost in lives and dollars would keep any future administration from going down that road again.
"I was wrong."
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