(CNN) -- Former presidential nominee and Sen. George McGovern has been admitted to a hospice in Sioux Falls, South Dakota, a spokeswoman for the facility said Monday.
"The family of Sen. McGovern wishes to extend their gratitude and appreciation for the many prayers and well wishes and requests complete privacy at this time," said Lindsey Meyers, spokeswoman for Avera McKennan Hospital and University Health Center.
McGovern, 90, is best known for his unsuccessful 1972 campaign for president as the Democratic nominee against incumbent Republican Richard Nixon.
In 1972, 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.
"We mentioned Vietnam. That tore the Democratic Party in half," McGovern told CNN in 2006. "You were either a hawk or a dove. You -- you weren't allowed to be neutral."
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.
He represented South Dakota in the U.S. Senate and House before and after his presidential campaign, leaving the daily foray of politics after losing his 1980 bid for a fourth Senate term.
McGovern has remained active since, including an appointment by then-President Bill Clinton as an ambassador to the U.N. Food and Agriculture Organization and a 2001 appointment as the U.N.'s first global ambassador for hunger.
He met his wife, Eleanor, while at Dakota Wesleyan University in 1941, before he joined the Army. He flew 35 combat missions as a B-24 bomber pilot in Europe, and was awarded the Distinguished Flying Cross.
The McGoverns had five children, but one of their daughters died in 1994. Eleanor died in 2007.
CNN's Carma Hassan contributed to this story.