Progressive Bernie Sanders earned a decisive victory on Saturday in the Nevada caucuses, solidifying his frontrunner status in the race to choose the Democratic nominee to face US President Donald Trump in November's election.
Mr Sanders's win is a substantial accomplishment in a state seen as an important bellwether because it is the first diverse electorate to weigh in on the 2020 presidential race.
It also shows he has been able to broaden a coalition beyond the narrow limits of leftist voters, denying the argument that he would not be able to bridge the divide between progressives and centrists.
By late Saturday, he was comfortably ahead with half of all precincts reporting.
The senator from Vermont was leading with about 46 per cent, followed by former vice president Joe Biden at 19 per cent.
South Bend, Indiana's former mayor Pete Buttigieg, who scored a shock narrow win in Iowa to start the race nearly three weeks ago, stood in third at 15 per cent.
The two female US senators in the running, progressive Elizabeth Warren and pragmatist Amy Klobuchar, were on 10 and 4 per cent.
Mr Sanders was quick to claim victory, saying his "multi-generational, multi-racial coalition" that won Nevada was "going to sweep this country".
His progressive policies, including universal health care, higher taxes on the wealthy and corporations, and raising the minimum wage have struck a chord with millions of Americans.
"The American people are sick and tired of a government that is based on greed, corruption and lies," he told a raucous rally.
"They want an administration that is based on the principles of justice."
Former vice president Joe Biden, desperate to right a listing ship after miserable showings in the first two states, said he felt "really good" about his Nevada finish and should not be counted out.
"We're alive and we're coming back," the one-time frontrunner said. "We're going on to South Carolina to win and then we're going to take this back."
South Carolina has a majority black Democratic electorate, and Mr Biden leads polling there.
His popularity among African-Americans is due in part to his eight years as popular president Barack Obama's deputy.
"Joe to me is like a thoroughbred, a horse that's gonna come in and that's gonna overtake whoever is the favourite," Air Force retiree Wilbert Wilcox said.
"He has the stamina going for him. I'm looking for him to really surprise some people."
Mr Sanders leads national polls with an average of 28 per cent support.
That is 11 points ahead of Mr Biden and 13 points clear of billionaire media tycoon Michael Bloomberg, the former mayor of New York who skipped campaigning in the four early states, including Nevada, to focus on Super Tuesday.
Mr Sanders has been largely unchecked by opponents who have focused more on blunting the advance of Mr Bloomberg, who has poured hundreds of millions of dollars of his own money into campaign advertising.
Ms Warren, speaking late on Saturday at a large rally in Washington state, which votes on March 10, pledged to stay in the fight despite a third straight mediocre showing.
She repeated her attacks on Mr Bloomberg, accusing him of seeking to "buy this election".
