SIOUX FALLS, S.D. – George McGovern once joked that he had wanted to run for president in the worst way — and that he had done so.

It was a campaign in 1972 dishonored by Watergate, a scandal that fully unfurled too late to knock Republican President Richard M. Nixon from his place as a commanding favorite for re-election. The South Dakota senator tried to make an issue out of the bungled attempt to wiretap the offices of the Democratic National Committee, calling Nixon the most corrupt president in history.

But the Democrat could not escape the embarrassing missteps of his own campaign. The most torturous was the selection of Missouri Sen. Thomas F. Eagleton as the vice presidential nominee and, 18 days later, following the disclosure that Eagleton had undergone electroshock therapy for depression, the decision to drop him from the ticket despite having pledged to back him “1,000 percent.”

It was at once the most memorable and the most damaging line of his campaign, and called “possibly the most single damaging faux pas ever made by a presidential candidate” by the late political writer Theodore H. White.

With R. Sargent Shriver as his running mate, McGovern went on to carry only Massachusetts and the District of Columbia, winning just 38 percent of the popular vote in one of the biggest landslides losses in American presidential history.

McGovern noted at an event with Eagleton in 2005 that Nixon and his running mate, Spiro Agnew, would both ultimately resign. He joked, “If we had run in ’74 instead of ’72, it would have been a piece of cake.”

A proud liberal who had argued fervently against the Vietnam War as a Democratic senator from South Dakota and three-time candidate for president, McGovern died at 5:15 a.m. Sunday at a Sioux Falls hospice, family spokesman Steve Hilde- brand told The Associated Press. McGovern was 90.

Hildebrand said he was surrounded by family and lifelong friends when he died.

“We are blessed to know that our father lived a long, successful and productive life advocating for the hungry, being a progressive voice for millions and fighting for peace,” the family said in a statement.

A decorated World War II bomber pilot, McGovern said he learned to hate war by waging it. In his disastrous race against Nixon, he promised to end the Vietnam War and cut defense spending by billions of dollars. He helped create the Food for Peace program and spent much of his career believing the United States should be more accommodating to the former Soviet Union.

Never a showman, he made his case with a style as plain as the prairies where he grew up, sounding often more like the Methodist minister he’d once studied to become than a longtime U.S. senator and three-time candidate for president.

And he never shied from the word “liberal,” even as other Democrats blanched at the word and Republicans used it as an epithet.

“I am a liberal and always have been,” McGovern said in 2001. “Just not the wild-eyed character the Republicans made me out to be.”

McGovern’s campaign, nevertheless, left a lasting imprint on American politics. Determined not to make the same mistake, presidential nominees have since intensely investigated their choices for vice president. Former President Bill Clinton got his start in politics when he signed on as a campaign worker for McGovern in 1972 and is among the legion of Democrats who credit him with inspiring them to public service.

“I believe no other presidential candidate ever has had such an enduring impact in defeat,” Clinton said in 2006 at the dedication of McGovern’s library in Mitchell, S.D. “Senator, the fires you lit then still burn in countless hearts.”

George Stanley McGovern was born on July 19, 1922, in the small farm town of Avon, S.D., the son of a Methodist pastor. He was raised in Mitchell, shy and quiet until he was recruited for the high school debate team and found his niche. He enrolled at Dakota Wesleyan University in his hometown and, already a private pilot, volunteered for the Army Air Force soon after the attack on Pearl Harbor.

He married Eleanor Stegeberg before being sent to Italy, which would be his base for the 35 missions he flew in the B-24 Liberator christened the “Dakota Queen” after his new bride.

His plane was hit during at least two missions, yet he was able to get it back safely, earning the Distinguished Flying Cross and the Air Medal.

McGovern returned to Mitchell and graduated from Dakota Wesleyan after the war’s end, and after a year of divinity school, switched to the study of history and political science at Northwestern University. He earned his master’s and doctoral degrees, returned to Dakota Wesleyan to teach history and government, and switched from his family’s Republican roots to the Democratic Party.

“I think it was my study of history that convinced me that the Democratic Party was more on the side of the average American,” he said.

McGovern, who had gotten into Democratic politics as a campaign volunteer, left teaching in 1953 to become executive secretary of the South Dakota Democratic Party. Three years later, he won an upset election to the House; he served two terms and left to run for Senate.

President John F. Kennedy named McGovern head of the Food for Peace program. He made a second Senate bid in 1962, unseating Sen. Joe Bottum by just 597 votes.

While McGovern continued to vote to pay for the Vietnam War, he did so while speaking against it. As the war escalated, so did his opposition.

President Obama remembered McGovern in a statement Sunday as “a statesman of great conscience and conviction.”

“When the people of South Dakota sent him to Washington, this hero of war became a champion for peace,” Obama said. “And after his career in Congress, he became a leading voice in the fight against hunger.”

McGovern first sought the Democratic presidential nomination late in the 1968 campaign, and made a third, longshot bid for the nomination in 1984.

After losing his bid for a fourth Senate term in 1980, McGovern went on to teach and lecture at universities, and to found a liberal political action committee.

McGovern served as U.S. ambassador to the Rome-based United Nation’s food agencies from 1998 to 2001 and spent his later years working to feed needy children around the world. He and former Republican Sen. Bob Dole collaborated to create an international food for education and child nutrition program, for which they shared the 2008 World Food Prize.