Following a tight race, former secretary Hillary Clinton defeated senator Bernie Sanders in Nevada. The Washington Post’s reporter Abby Phillip breaks down why this victory was critical for Clinton and what this means for both candidates going into South Carolina. (Alice Li/The Washington Post)

Following a tight race, former secretary Hillary Clinton defeated senator Bernie Sanders in Nevada. The Washington Post’s reporter Abby Phillip breaks down why this victory was critical for Clinton and what this means for both candidates going into South Carolina. (Alice Li/The Washington Post)

Hillary Clinton held off a powerful late challenge from rival Sen. Bernie Sanders in Nevada’s Democratic caucus vote Saturday, securing a narrow victory that helps the former secretary of state regain momentum after a crushing defeat in New Hampshire.

Nevada was the first state to test support among minority voters, who have long been expected to be in Clinton’s camp. As it turned out, preliminary entrance polls showed Latinos favoring Sanders, despite having voted for Clinton 2-to-1 when she ran in 2008. African American voters, meanwhile, appear to have overwhelmingly supported Clinton — a development that could bode extremely well for her given the run of Southern states with large black electorates voting in the coming weeks.

“Some may have doubted us, but we never doubted each other,” Clinton told supporters gathered at a Las Vegas hotel ballroom. Clinton congratulated Sanders on a close election, but she got in a few digs, too.

“It can’t just be about what we’re going to give to you; it has to be about what we are going to build together,” she said in an unmistakable reference to Sanders’s large and expensive plans for government-run health care, college and more.

Clinton’s campaign cast doubt on the strength of Sanders’s support among Hispanics, pointing to majority-Latino precincts that she won.

Sanders used his concession speech to denounce the “corrupt campaign finance system” and the nation’s vast inequality between the “top 1 percent” of the economy and everyone else.

“The wind is at our backs,” Sanders said. “We have the momentum.” He predicted several victories in upcoming state primary contests and, ultimately, “one of the great political upsets in the history of the United States.”

Saturday’s results seemed to render that promise more difficult to achieve.

Sanders had steadily eroded Clinton’s double-digit lead in Nevada, the first state with a racially diverse population to cast primary votes this year. Slightly more than a quarter of the state’s population is Hispanic, and the state is also home to sizable African American and Native American populations.

A Sanders victory in Nevada would have suggested a reach far beyond his core base of white liberals — and rocked the premise that Clinton’s national lead was insurmountable. Instead, Clinton’s strong showing among African American voters in Nevada suggests that despite inroads among Hispanic voters, Sanders faces an even more difficult test in the next contest, in South Carolina next Saturday.

With most precincts reporting, Clinton was winning with 52 percent of the vote overall to Sanders’s 48 percent. But according to preliminary entrance polls reported by CNN, she won among black Democrats by a whopping 76 percent to 22 percent. African Americans made up 13 percent of the electorate, according to the entrance poll, while 19 percent were Hispanic and 59 percent were white. Sanders held an eight-point edge among Hispanic voters, who accounted for roughly 1 in 5 caucus-goers, and the two candidates split white voters about evenly.

“In the five NV precincts with the highest percentages of African American registrants, Clinton won all the delegates, 76-0,” her spokesman, Brian Fallon, said in a tweet shortly after the results were known.

1 of 24 Full Screen Autoplay Close Skip Ad × What it looked like on the ground in Nevada for the Democratic caucuses View Photos Hillary Clinton held off a late challenge from rival Bernie Sanders in the Silver State. Caption Hillary Clinton held off a late challenge from rival Bernie Sanders in the Silver State. Feb. 20, 2016 Democratic presidential candidate Hillary Clinton hugs her Nevada campaign director, Emmy Ruiz, while approaching the stage at Caesars Palace in Las Vegas to deliver a speech after winning the state’s Democratic caucuses. Melina Mara/The Washington Post Buy Photo Wait 1 second to continue.

Clinton has enjoyed a large lead among South Carolina African Americans, who in 2008 made up more than half the Democratic primary electorate.

And on March 1, when more delegates will be awarded in Super Tuesday voting than at any other time in the political calendar, black voters make up significant parts of the Democratic electorate in Alabama, Georgia, Texas, Arkansas and Virginia. Sanders has a better chance of winning the other Super Tuesday states — Colorado, Massachusetts, Minnesota, Oklahoma and his home state of Vermont — which have relatively small black populations.

Sanders planned to campaign in South Carolina on Sunday, but he has scheduled events Monday in Massachusetts.

“We’re going to target the states where we’re strongest and compete for delegates everywhere,” said Jeff Weaver, Sanders’s campaign manager.

Clinton flew directly to Texas for a campaign rally later Saturday and will be in South Carolina in the coming week.

Clinton has now barely won two of the first three states to cast presidential selection votes, and she lost the other badly. Sanders’s growing momentum in recent weeks has exposed flaws in Clinton’s candidacy and threatened her carefully constructed strategy that presented her as the presumed front-runner and heir to President Obama’s legacy.

The Nevada vote, however, gives weight to the claim by Clinton allies that the wave of anti-establishment fervor carrying Sanders would slow in states with fewer white voters.

Sanders, who represents a state that is 95 percent white, has never in his four-decade political career had to court minority voters. His advisers said they were confident that his economic message would break through with younger and working-class voters — two constituencies he has connected with in other states — regardless of race.

Clinton supporters gathered for her victory party in a ballroom at Caesars Palace and erupted in cheers and chants of “Hill-a-ry! Hill-a-ry!” as results flashed on the televisions.

“I told ya!” said Michael Airington, 57, a Clinton supporter. “She needed this. Now she’s going to sweep South Carolina!”

Airington attributed the closeness of the vote to younger Democrats who were too young to know much about Clinton’s work during her husband’s presidency in the 1990s.

“She needs to recalibrate with the millennials and let them know she was for everything Bernie is for before Bernie was,” Airington said.

Indeed, voters younger than 30 preferred Sanders 82 percent to 14 percent, and those younger than 45 picked Sanders 62 percent to 35 percent, according to the CNN exit poll data.

Weaver said Sanders’s now-proven ability to court Latinos should help his prospects going forward in states including Texas, Colorado, Arizona, New Mexico and California. He also said that the loss in Nevada will not affect Sanders’s plans to remain in the race through the Democratic National Convention.

Clinton’s first campaign trip to Nevada, weeks after she entered the race in April, was intended as an outreach primarily to Hispanics and chiefly around the issue of immigration. She met with young people protected from deportation by Obama’s executive actions, and she pledged to seek a path to citizenship for illegal immigrants.

Nevada led the nation in home foreclosures and was hit hard by bankruptcies during the Great Recession. Sanders’s heavy focus on an economy “rigged” to benefit the wealthy and powerful interests had resonated in a state where many residents blamed Wall Street and large mortgage companies for their reversals.

In the closing days, his campaign aired a 30-second ad with foreclosure signs and aerial shots of decimated neighborhoods narrated by Erin Bilbray, the daughter of a former congressman, who relayed how her neighbors were hurt by the crisis.

“I’ve watched as the house across the street has sat empty for over six years,” says Bilbray, a Democratic National Committee member and former Clinton supporter. “I’ve watched good friends have their homes foreclosed on. People are still really suffering, and they’re looking for somebody who is going to create bold change.”

The senator from Vermont also repeatedly pointed to Clinton’s ties to big financial institutions, as he did again Saturday by noting that a super PAC supporting Clinton receives what he called Wall Street donations.

But in the days leading up to the caucus vote, immigration was the main point of argument between the two campaigns.

Clinton and her surrogates argued that Sanders was a latecomer to championing the rights of illegal immigrants. Clinton allies have made the same claim about Sanders’s efforts to win over African Americans elsewhere.

“He is a very strong candidate. He had a lot of committed supporters,” Clinton communications director Jennifer Palmieri said Saturday. “He is a real force, and he will continue to be a strong candidate, so we are grateful for this win, but we know we have 47 more states.”

About 80,000 people showed up for the Nevada caucuses on Saturday, a significant drop-off, compared with 2008, the last time there was a competitive Democratic race, according to officials at the Nevada Democratic Party.