WASHINGTON: Former US senator George McGovern, a liberal icon who vowed to end the Vietnam War but lost a landslide presidential election to Richard Nixon in 1972, died early Sunday at the age of 90.

The family said in a statement that the liberal standard-bearer died at about 5:15 am (1015 GMT) at the Dougherty Hospice House in Sioux Falls, South Dakota, surrounded by family and life-long friends.

“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 statement said.

“He continued giving speeches, writing and advising all the way up to and past his 90th birthday, which he celebrated this summer.”According to the family, funeral services will be held in Sioux Falls but no exact date was given.

The three-term senator was widely credited with bringing women, youth and minorities into the Democratic Party in a broad-based White House campaign that foundered after revelations of his running mate's battle with mental illness.

President Nixon went on to end direct US military involvement in Vietnam with the signing of the Paris Peace Accords in January 1973, but resigned in disgrace the following year over the Watergate scandal.

McGovern's 1972 campaign was built on a grassroots movement that helped expand the Democratic Party from its base among the urban white working class and unions to a big tent encompassing women, minorities and student activists.

Both Bill and Hillary Clinton got their start in politics working for the campaign when they were in their mid-20s, and many McGovern supporters returned the favor during Hillary's primary battle with Barack Obama in 2008.

McGovern's campaign harnessed growing opposition to the Vietnam War but suffered a fatal blow when his running mate, Missouri Senator Thomas Eagleton, was forced to quit the ticket after it emerged that he had been hospitalized on three occasions and given electroshock therapy.

McGovern had not known about Eagleton's history of depression when he chose him, which in part explains why candidates now typically conduct exhaustive background checks on prospective running mates.

McGovern lost in one of the most dramatic landslides in US history, winning only Massachusetts and the District of Columbia. The term “McGovern liberal”became a favorite taunt of Republicans for decades.

But Nixon, a Republican, was forced to resign in disgrace two years later in the infamous Watergate scandal, named for the burglary of McGovern's party headquarters less than five months before his election defeat.

Born on July 19, 1922 in Avon, South Dakota, McGovern enlisted in the US Army Air Corps at the age of 19, flying 35 missions as a B-24 bomber pilot in Europe during World War II. He earned a PhD from Northwestern University in 1953.

McGovern served in the US House of Representatives from 1957 to 1961 and as special assistant in charge of the Food for Peace Program under president John F. Kennedy in 1961.

He was elected to the US Senate the following year, eventually serving three six-year terms, and championing the fight against world hunger.

After leaving the Senate in 1981, McGovern served as a visiting professor at several universities and was president of the Middle East Policy Council, a Washington-based think tank, in the 1990s.

In 1994, his daughter Terry, a mother of two who had long suffered from alcoholism, froze to death when she passed out in a Wisconsin snowbank.

McGovern later wrote a book about her struggle with substance abuse and used the proceeds to build a treatment center for alcoholic women and children.

He had four other children with Eleanor, his wife of 63 years, who died in 2007.

From 1998 to 2001, McGovern served as US ambassador to the UN Food and Agricultural Organization in Rome. Then-president Clinton awarded him the Presidential Medal of Freedom in August 2000.

McGovern lamented his 1972 defeat in a Washington Post op-ed last month, saying: “I wanted to win for our party, our young soldiers, and the men and women of goodwill disaffected by Watergate and turned off by the power of big money in politics.”

But “at the wise old age of 90, I can say that losing the presidency was one chapter in a long, complex and richly happy life in which I learned that you can't always control all the outcomes.”