Bernie Sanders scored a decisive victory in the Democratic presidential caucuses in Nevada on Saturday and gained a fresh burst of momentum, while Joe Biden appeared headed to a second-place finish that will give his struggling campaign new hope.
Sanders, a senator from Vermont, had 45% of the county convention delegates in Nevada with about 4% of the precincts reported, and television networks predicted he would cruise to an easy win.
But there were long delays getting more results reported, more than five hours after the caucuses started.
Biden, the former vice president, appeared headed to a badly needed strong showing after poor finishes in the first two contests in Iowa and New Hampshire for the party's nomination to face Republican President Donald Trump in the November election.
He was a distant second to Sanders with 19% of the vote, but ahead of former Mayor Pete Buttigieg of South Bend, Indiana, in third with 16%.
"The press is ready to declare people dead quickly, but we're alive and we're coming back and we're gonna win," Biden told supporters in Las Vegas on Saturday night.
Senator Elizabeth Warren was trailing in a disappointing fourth with 11% in Nevada, where voters poured into more than 250 sites around the state.
Sanders showed signs of expanding his support beyond his core supporters, riding a wave of backing from most age groups, Latinos and union members to victory in Nevada. Entrance polls also showed heavy backing for his government-run Medicare for All healthcare plan.
"We have put together a multi-generational, multiracial coalition that is going to not only win in Nevada, it's going to sweep the country," Sanders told cheering supporters in San Antonio, Texas.
Buttigieg, however, told his supporters in Las Vegas that Democrats should stop and reconsider nominating Sanders, a self-identified democratic socialist that he portrayed as an ideologue.
"We can prioritize either ideological purity or inclusive victory. We can either call people names online or we can call them into our movement. We can either tighten a narrow and hardcore base or open the tent to a new, broad, big-hearted American coalition," Buttigieg said.
After a technical meltdown delayed results during the Iowa caucuses, Nevada Democratic Party officials promised that a revised reporting system using a telephone hotline and photos of caucus reporting sheets would ensure a smoother process.
But precinct chairs at some caucuses reported long waits on the phone lines. Larry Van, a retired pharmacist who was the volunteer secretary at a precinct that went to Biden, said he called the phone number to report results eight times before he eventually got through.
In the final result of a caucus at the famed Bellagio hotel on the Las Vegas strip, Sanders finished with 76 votes, Biden had 45 and no other candidate ended with a vote.
Workers at the hotel, who are members of the Culinary Workers Union, streamed out of the caucus after backing Sanders despite their leadership expressing reservations about his healthcare plan.
"I went for Bernie. I'm not big into politics, but I like the things he's going for: student loan debt, schools, free healthcare," said Aleiza Smith, 22, a housekeeper at the Bellagio.
Four days of early voting in Nevada this week drew more than 75,000 Democrats, more than half first-time voters, putting the party in position to surpass the turnout record of 118,000 in 2008, when Barack Obama's candidacy electrified the party.
But those early votes had to be counted along with those cast on Saturday, complicating the process.
An entrance poll by the Edison Research agency showed six in 10 Nevada voters at the caucuses backed the Medicare for All proposal, a version of which is also supported by Warren.
Six out of 10 caucus-goers wanted someone who can beat Trump more than someone who agrees with them on major issues, according to the poll.
The entrance poll showed that Sanders led in Nevada across all age groups except for those older than 65. Around 54% of Latino voters said they backed him, while 24% of college-educated white women and 34% of those who have a union member in their families supported him.
The Nevada caucuses came a day after news broke that Sanders had been briefed by U.S. officials that Russia was trying to help his campaign as part of an effort to interfere with the 2020 presidential election.
While Sanders' rivals tried to blunt his momentum in the caucuses, they each faced significant challenges of their own.
Biden and Warren were looking to jump-start struggling campaigns after poor finishes in the first two states, while Buttigieg and Senator Amy Klobuchar are hoping to prove they can appeal to Nevada's more diverse electorate.
Trump, who lost Nevada to Democrat Hillary Clinton in 2016, tweeted on Saturday that he expected to win in Nevada in the general election in November and alluded to the reports that a Russian disinformation effort was supporting Sanders.
At a Democratic debate in Nevada on Wednesday, candidates launched scathing attacks on Michael Bloomberg, the billionaire former mayor of New York City, who has been rising in the polls on the back of a self-funded advertising blitz but is not competing in Nevada.
The next primary will be on Feb. 29 in South Carolina, followed by the Super Tuesday contests in 14 states on March 3 that pick more than one-third of the pledged delegates who will help select a Democratic nominee.
Nevada is the first nominating state with a diverse population after contests in predominantly white Iowa and New Hampshire.