The AP is calling Nevada for Hillary Clinton, who squeaked by with 52.2 percent of the vote, a narrow margin over Bernie Sanders, who took 47.7 percent.
Sanders won many of the northern counties that favored President Barack Obama, then a senator, when he ran against Clinton in 2008. Clinton was buoyed by Clark County, where almost 75 percent of Nevada's 2.8 million residents live.
As the Los Angeles Times reported from the road, some precincts in Nevada were breaking caucus ties by pulling cards out of a deck.
Meanwhile, entrance polls found that voters were split between "empathy and experience," as the LAT's David Lauter wrote.
The Guardian also notes that Clinton has something new to worry about:
Sanders won 54% of the Latino vote, according to the sample data, compared to Clinton’s 43%. That is a worrying result for Clinton, who has staked her campaign on the promise of winning minority voters.
Some Latino voters, particularly younger people and low-wage workers, appeared to be opting for Sanders in the final weeks of the campaign. In the final 48 hours of the campaign, the Clinton camp ramped up a negative push against Sanders, questioning his commitment to immigration reform and claiming he neglected communities in his three decades in public office.
On Twitter, Sanders thanked the people of Nevada for "the support they have given us and the boost that their support will give us as we go forward."
"I am very proud of the campaign we ran," he said. "Five weeks ago we were 25 points behind and we ended up in a very close election."
In an email to supporters, he noted that Nevada "was supposed to be a state 'tailor made' for the Clinton campaign, and a place she once led by almost 40 points. But today, we sent a message that will stun the political and financial establishment of this country: our campaign can win anywhere."
Additional precincts are reporting. As of 7pm EST, the results gave Clinton 5,259 county convention delegates, and Sanders 4,805.
Here's how NBC News is breaking down the results:
Hillary Clinton eked out a tight win in Nevada by relying on key groups that supported her in prior contests - particularly women and older voters. Clinton took 71 percent of the vote among caucus-goers age 65 and older, and 55 percent of female voters. She also won six-in-10 voters who attended graduate school. While Clinton lost the Hispanic vote to Sanders, she won the overall nonwhite vote because of strong support from black voters.
Among caucus-goers who said they were looking for a candidate with the right experience, Clinton won 91 percent of the vote. She took more than three-fourths of the vote among those who were primarily concerned with a candidate who was best positioned to win the general election. She also won six-in-10 voters who said their top issue is health care.
The latest Democratic presidential caucus is underway in Nevada, a critical state for both Hillary Clinton and Bernie Sanders, who recent polls have shown are neck-and-neck there and nationwide.
In Henderson on Friday night, Sanders told a crowd of more than 2,000 supporters that they had the chance to "make history" on Saturday, urging them to turn out in large numbers and "help us move the political revolution forward."
Nevada, previously considered a firewall for Clinton, is a notoriously unpredictable caucus state. The 2016 election has also seen the Latino vote splintering between the two Democratic rivals. But as Common Dreams reported on Friday, recent endorsements in the state indicate a Sanders surge may be on the way.
"Sanders needs to prove he can win over Latinos, Asian-Americans, and African-Americans—there’s no other way that he can seriously compete for the nomination," wrote Jeet Heer at The New Republic. "Clinton, conversely, needs to prove that her 'firewall' of non-white support, which she’s also counting on in the upcoming Southern primaries, is going to be strong enough to block Sanders."
Meanwhile, voting is also underway in the South Carolina GOP primary, where Donald Trump is expected to win.
The Democrats will primary in South Carolina next week. A win for Sanders in Nevada "would raise more questions about Clinton’s appeal and add to the pressure on her to score a big victory in South Carolina," write Dan Balz, Abby Phillip and Jose DelReal at the Washington Post.
Check back for updates.