NORTH LAS VEGAS, Nev. — The stage was set for Bernie Sanders to make a splashy introduction to Latino voters.

At a rally Sunday night on a soccer field in this heavily Latino suburb of Las Vegas, a 10-piece mariachi band performed traditional ranchera songs such as “México Lindo y Querido.” A college student spoke movingly about her parents immigrating here illegally. “The original dreamers,” she called them. And a organizer for a culinary union introduced Sanders in Spanish: “Viva, Bernie! Viva, Bernie!” 

But when the iconoclastic Democratic presidential candidate took the stage, what he saw was more familiar: a sea of white people — young and old, idealistic students, frustrated liberals and free-spirited hippies.

There were plenty of Latinos, too. Antonia Martinez came to the rally because her 24-year-old daughter, Yadira, had been talking so much about the senator from Vermont that she wanted to see what all the fuss was about. She left as a convert.

But overall, this was a primarily white crowd, underscoring Sanders’s challenges in diversifying his coalition.

Sunday’s rally was part of his concerted courtship of Latino voters, which also included an appearance Monday before a conference of immigration reform advocates. Sanders’s campaign is airing Spanish-language radio ads, hiring prominent Latino organizers and expanding its footprint in Nevada. Sanders also has been meeting privately with immigrant families to better understand their hardships and priorities.

Of the four early-voting states, Nevada — which plans to hold its caucuses on Feb. 20 — has the highest percentage of Latino voters. The caucuses here are a test of organizational might, and Hillary Rodham Clinton, who won them in 2008, has had a large presence here since April.

Clinton has been cultivating relationships in the Latino community for decades, since she and then-boyfriend Bill Clinton canvassed South Texas to register black and Hispanic voters in 1972.

Martin O’Malley, the third Democratic candidate, built strong ties with Latinos as governor of Maryland, where he signed a state Dream Act and other laws to help what he terms “New American immigrants.”

For Sanders, the kind of coalition politics practiced by Clinton and O’Malley is somewhat foreign. He has long represented one of the whitest states in the union. At the Latino rally, Sanders self-effacingly called himself “some guy you’ve never heard of.”

But the road to the Democratic nomination goes through racially diverse states, including early-voting South Carolina and Nevada, so Sanders is making explicit appeals to black and Latino voters.

“If we stand together as Latinos, as immigrants, as African Americans, as whites, as Asian Americans — no matter how much money and how much power the billionaire class has, there is nothing that we cannot accomplish in creating the kind of life our people deserve,” Sanders told activists Monday at a candidates’ forum held in Las Vegas by the Fair Immigration Reform Movement. People responded with shouts of “Sí, se puede!” — an echo of President Obama’s “Yes, we can!” campaign motto.

On Sunday night, Sanders wove into his stump speech a detailed and forceful call for comprehensive immigration reform, and he repeated the points at Monday’s forum. He spoke about his Polish immigrant father and decried the rhetoric coming from some Republican candidates.

“Let me be very clear in saying that it is not an American value for Donald Trump or anyone else in this country to refer to people from Mexico as ‘rapists’ and ‘criminals,’ ” he said. “That is old-fashioned racism, and we will not tolerate it.”

Sanders said that as president, he would push for immigration legislation that provides a path to citizenship. But if Congress did not act, he said, he would bolster the executive actions taken by Obama.

“Undocumented workers are doing the extremely difficult work of harvesting our crops, building our homes, cooking our meals and caring for our children,” he said. “They are part of the fabric of our country.”

Sanders said he would increase prosecutorial discretion and dismantle “inhumane deportation programs,” including closing privately owned detention centers. And he said he would give asylum to victims of domestic violence as well as unaccompanied minors from Latin America.

As he read his proposals from notes at the lectern, Sanders received loud bursts of applause. There were chants of “Bernie! Bernie! Bernie!”

At the immigration forum, however, O’Malley slammed Sanders and Clinton, saying they were too cautious and accusing both of “poll-tested triangulation.”

O’Malley, who is trailing his two rivals, pointed to Sanders’s 2007 comments to Lou Dobbs, then a CNN anchor and now a Fox Business Network personality whose views are controversial among many immigrants.

“When comprehensive immigration reform was up for a vote in the Congress, Senator Sanders went on Lou Dobbs’s show — are you familiar with Lou Dobbs? — and said that immigrants take our jobs and depress our wages,” O’Malley said. “Not only are those statements flat-out wrong, they actually harm the consensus.”

Talking to reporters, O’Malley questioned the motivations of Sanders and Clinton on immigration. “Is this a priority for the two of them because it’s an election year, or is this something they truly believe?” he asked.

Sanders’s advisers acknowledge the challenge they face in persuading Latino voters but believe many will be drawn to his anti-establishment message.

“We have a great opportunity to present our ideas, our platform to the American population,” said Arturo Carmona, the campaign’s Latino outreach director. “People are sick and tired of establishment politics, more of the same, and the more we talk to people, the more we feel they are buying our message and getting involved.” 

Sanders focused mostly this summer on Iowa and New Hampshire and building a national profile. He only recently began assembling a staff in Nevada, although aides said he plans to open 10 field offices in the state in the next couple of weeks.

Sanders’s state director, Jim Farrell, left his position unexpectedly because of a family issue, the campaign announced Sunday. Farrell was replaced by Joan Kato. Meanwhile, Sanders has made a number of Latino hires recently here and nationally, including Erika Andiola and Cesar Vargas, both DREAMer activists.

Watching Sanders here Sunday, Raúl Martinez, 44, said he was drawn to the senator’s authenticity. “He’s very genuine,” he said. “He’s been saying the same thing for 20 years and I trust him. That’s rare.”

Martinez said he hopes fellow Latinos see what he sees in Sanders.

“This is North Las Vegas. They’ve got the mariachi band and everything,” he said. “I hope it’s effective — I really do.”