NORTH LAS VEGAS — The people lined up on stage waiting for Marco Rubio to arrive at the Texas Station casino in North Las Vegas on Sunday night looked like a phalanx of soldiers dressed by Men’s Wearhouse, and the Florida senator liked the way they looked up there, I guarantee it.

The assembled were the living, breathing references section on Rubio’s résumé, personifications of the steady stream of endorsements that keep coming in for him — despite his perpetual second place-ness to Donald Trump — now that Jeb Bush has departed. Before the candidate took the stage, speakers included a senator, a congressman, a “Pawn Stars” star and a former New Kid on the Block (hint: the Wahlberg that’s not Mark); all were marshaled to and from the mic by an energetic man in rimless glasses with sandy-blond hair, Lt. Gov. Mark Hutchison.

Hutchison is, among other things, the chair of Rubio’s Nevada campaign and a prominent member of the Church of Jesus Christ of Latter-day Saints. These two facts are not unimportant in the context of today’s Republican caucuses in Nevada. Mormons are only 4 percent of Nevada’s population, but they have exercised outsize influence in the state’s past two caucuses, accounting for 25 percent of Republican participants in 2012 and 26 percent in 2008; Mitt Romney, America’s most famous Mormon, won their vote by 88 and 95 percent, respectively.

But there is no Romney on the ticket in 2016, meaning the Mormon vote is seen as a prize among the Republican candidates, with Rubio and Ted Cruz each making gambits. The same night Rubio stumped amid the slot machines, Cruz was introduced at a rally in Henderson, Nevada, by radio personality Glenn Beck, who got a cheer from the crowd when he said he was Mormon. “Well that’s a very different reaction,” he said.

The Mormon community makes up a small slice of the electoral pie, but their reach is significant, according to Quin Monson, a political scientist at Brigham Young University who has studied the community’s voting habits. “In caucus situations where it’s a little more effort and civic responsibility and organizing ability, this is where the Mormons can be particularly effective,” he said.

Listen to the latest episode of the FiveThirtyEight politics podcast.

Caucuses involve standing up and stumping for a candidate, and that, said David Campbell, a political scientist at Notre Dame and Monson’s co-author, is a natural fit for members of the LDS Church. “Mormons as a group are very comfortable with public speaking; that’s a regular part of the faith,” he said, citing the rotating talks given at weekly church sermons by members of the congregation. “The mission experience just kind of ramps that up,” Campbell added. “You’ve either spent 18 months or two years of your life approaching complete strangers.”

In 1960, John F. Kennedy won close to 80 percent of the Catholic vote in his race against Richard Nixon, according to estimates. By the time 1972 rolled around, Nixon won 52 percent Catholics. The world changed in those 12 years, and Catholics went from being identity-politics voters to those grappling with the issues-based implications of their faith in public life. While Mormons are overwhelmingly Republican, they are generally not knee-jerk party-liners, according to Monson, who called them “conservative with a twist.” Campbell noted that time spent overseas doing mission work means “Mormons as a group are actually more cosmopolitan than you might think.” That makes whatever way their vote swings this election an object of certain fascination.

There isn’t polling data that tells us which way Mormons might be leaning in this year’s Republican primary, but thanks to Trump’s something-there-is-that-doesn’t-love-a-wall campaign, hard-line rhetoric on immigration and refugees has become something of a staple in this campaign, and Mormons hold nuanced views on immigration. “The Church of Jesus Christ of Latter-day Saints is concerned that any state legislation that only contains enforcement provisions is likely to fall short of the high moral standard of treating each other as children of God,” a 2011 statement from the Mormon Church read. “The Church supports an approach where undocumented immigrants are allowed to square themselves with the law and continue to work without this necessarily leading to citizenship.”

This stance is reflected by split Mormon public opinion on immigration. A Pew survey published in 2012 showed that 45 percent of LDS Church members thought immigrants strengthened the country and 41 percent said they were a “burden.” This tracks with the public’s views on immigration, but not Republicans’; according to a 2015 Pew survey, 43 percent of Republicans were more likely to vote for a candidate who would deport all illegal immigrants. In October, in the midst of the Syrian refugee crisis, the Church released a letter expressing support for those fleeing. “It didn’t mention Trump by name, the Church is very careful,” Monson said. “But the timing was unmistakable.” Harassed and misunderstood for over a century — their founding father was killed by an angry mob, after all — Mormons are acutely sensitive to the plight of the outsider.

Rubio’s past attempts at immigration reform could make him a favorite with Mormons, but Cruz’s ardent Constitutionalism is a boon in the LDS community as well; it is a theological tenet of the religion that the Constitution was divinely inspired. “You will often find Mormons talking about the Constitution in very reverential terms,” Campbell said. “That’s why the term ‘Constitutional conservative’ resonates so well.” (Utah Sen. Mike Lee, also a Mormon, has built a career on this foundation.)

Rubio himself went to a Mormon church for a time when his family lived in Nevada. While he didn’t explicitly bring that up at the Sunday night rally, he did spend an inordinate amount of time (for a stump speech) pointing out how many family members were present and detailing the Las Vegas chapter of his life. “I’d never seen mountains before, and they looked like cardboard cutouts,” he said of getting off the plane from Miami. “My skin had never been so dry.”

The establishment on the stage behind him laughed politely. At about the same time, “Mitt Romney” started trending on Facebook: Rumors were flying that America’s most famous Mormon would soon endorse Rubio.