Ted Cruz is trying to drum up support in rural Nevada from Republicans angry at the federal government's control of most of the state's land.
Marco Rubio wants to lay claim to the Mormon vote that drove Mitt Romney's two big victories in presidential caucuses here.
And in a state with a large immigrant population, Donald Trump is tapping the resentment of white blue-collar Nevadans by promising to wall off Mexico.
Jeb Bush's exit from the Republican presidential race Saturday in effect turned Nevada into a three-man brawl, with Cruz and Rubio scrambling to break Trump's winning streak after victories in New Hampshire and South Carolina.
Over the weekend, Rubio's team started cajoling Bush's huge pool of big-money donors. The senator from Florida is the top-tier candidate most in danger of running out of money, newly released finance reports show.
Rubio has yet to win a state but is trying to be seen as the most viable mainstream conservative alternative to Trump, a case that would be easier to make if he performs well in Nevada.
Rubio and Cruz, a senator from Texas, have corralled high-profile Nevada supporters to vouch for their conservative purity.
Unlike Trump, they've hired top Nevada campaign consultants to build strong get-out-the-vote networks — often crucial in low-turnout caucuses. Trump's ramshackle operation in Iowa was a factor in Cruz defeating him in the Feb. 1 caucuses there.
But Trump has built a huge following in Nevada with his combative rhetoric on illegal immigration and economic unrest. The breadth and intensity of his support could offset any shortcomings in organization.
"I just don't know how you stop the raw enthusiasm behind Trump," said Zachary Moyle, the Nevada state director for GOP presidential hopeful John Kasich, the governor of Ohio.
Trump arrives in Las Vegas on Monday for a casino resort rally in an arena sometimes used for bull-riding competitions.
"I have a lot of property out there and a lot of great employees, and I think I should do well in Nevada," he said Sunday on CBS' "Face the Nation."
As elsewhere, the Manhattan billionaire will capitalize on the free media exposure he attracts as a reality television star. Fox News is giving him an hour Monday night on "Hannity." Trump's only other scheduled stop in Nevada is a lunchtime rally at a casino outside Reno on Tuesday, the day of the state's Republican caucuses.
The lone TV commercial that he is airing features a testimonial to Trump from Jamiel Shaw Sr., whose 17-year-old son was killed in Los Angeles by an immigrant in the country illegally.
Trump's appeal on immigration has resonated widely.
"When I talk to my truckers and ask who they like, I rarely hear anything different than Donald Trump," said Paul Enos, chief executive of the Nevada Trucking Assn., a group unaligned in the presidential race.
Most of the state's Republicans live in the Las Vegas and Reno areas, but Cruz is trying to dominate the state's rural outposts. At a sports bar Sunday in Pahrump, a remote desert town known for its brothels, Cruz reminded locals of his support for gun rights.
He also said it was ridiculous for the federal government to own nearly 85% of Nevada's land.
"I think we should send it back to the people," Cruz said.
At the Cruz campaign office in a Las Vegas strip mall, volunteers working the phones have been telling rural voters that the Texas senator was more amenable than Trump to the government shedding its public lands.
"If you're a rancher or a farmer out there, it's a life-or-death issue," said Dave McGowan, who oversees the office.
The Cruz team was telling voters of his vow to abolish the Internal Revenue Service. Cruz's prize endorsement in Nevada is state Atty. Gen. Adam Laxalt, a popular figure among conservatives.
For his part, Rubio is counting on outsize support among well-educated white suburban Republicans. He also hopes to draw a large share of Mormons. His Nevada chairman, Lt. Gov. Mark Hutchison, is Mormon.
The first-term senator won the endorsement of the Las Vegas Review-Journal, the newspaper recently bought by casino mogul Sheldon Adelson, a top Republican benefactor. But so far, Adelson has not put big money behind Rubio, and some party leaders doubt the endorsement's value.
"A hill of beans," said Heidi Smith, a former Republican National Committee member for Nevada, who is neutral in the race.
But Rubio's operation is robust, with staff and volunteers calling thousands of voters from offices in Las Vegas and Reno.
The callers, like Cruz's, work off lists of Republicans culled by strategists for demographic traits that make them good targets for the candidate's message. Once supporters are identified, volunteers call them again to ensure they know when and where to caucus.
In a Las Vegas strip mall on the same block as the Cruz office, Rubio volunteer Ken Hebert, a retired Navy man, made phone call No. 1,420 one day last week and logged the results on his laptop.
"He'd prefer not to tell me who he supports, but I know it's not Marco Rubio," Hebert said diplomatically.
The Nevada race will be a quick interlude before the GOP campaign spreads across the nation with March 1 contests in a dozen states. (Rubio was dashing through Tennessee and Arkansas on Sunday on his way to Las Vegas; Trump was holding a rally in Atlanta.)
Kasich, always a long shot here, is skipping Nevada, campaigning instead in Massachusetts and other states where he stands better prospects.
Retired neurosurgeon Ben Carson was making stops in Reno and Las Vegas on Sunday, but his base of evangelicals is nowhere near large enough to make him a serious contender here.
Barely 1 in 10 Republicans voted in the last two Nevada GOP caucuses, but party leaders expect a higher turnout this time, largely because of public interest in Trump.
"It looks like it may very well be epic this year," said Ed Williams, the Clark County Republican Party chairman. "At least by our standards."
Times staff writer Kurtis Lee contributed to this report.