(AP) - 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.

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

The family had said late last week that McGovern had become unresponsive while in hospice care.

Hildebrand said funeral services were to be held in Sioux Falls and details would be announced shortly.

McGovern could not escape the embarrassing missteps of his own campaign of 1972. 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.

After a hard day's campaigning - Nixon did virtually none - McGovern would complain to those around him that nobody was paying attention. With R. Sargent Shriver as his running mate, he 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.

"Tom and I ran into a little snag back in 1972 that in the light of my much advanced wisdom today, I think was vastly exaggerated," McGovern said at an event with Eagleton in 2005. Noting 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 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 longtime U.S. senator and three-time candidate for president he became.

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 interviewed and 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 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."