Trump's victory, which was quickly called by broadcast networks and later affirmed by the state Republican Party, showed not only that he has undeniable momentum, but that he holds broad geographic appeal.
After coming second in Iowa, in America's midwest, he went on to capture primaries in New Hampshire in the northeast and South Carolina in the south. Nevada was the first western contest.
"If you listen to the pundits, we weren't expected to win too much, and now we're winning, winning, winning the country," Trump said at a victory rally in Las Vegas.
Trump is expected to take the bulk of Nevada's 30 delegates, which would give him more than 80 before February ends, and dwarf the tallies of his closest rivals, U.S. Senator Ted Cruz of Texas and U.S. Senator Marco Rubio of Florida.
While more than 1,200 are needed to secure the Republican presidential nomination, Trump has a formidable head start.
Key primaries are ahead on Feb. 1 in states that include Alabama, Georgia, Tennessee, Texas, and Virginia, all states in which Trump could do well and further cement his front-running status.
Despite early reports on social media of procedural irregularities at many Nevada caucus sites, the Republican National Committee and the party's state chapter said voting was running smoothly.
Higher-than-normal turnout was reported, although historically, few of the state's citizens participate in the Republican caucus.
For weeks, Trump had been considered the favorite to win Nevada, although both Cruz and Rubio made strong bids to mount an upset.
Cruz attempted to appeal to the state's fierce libertarian wing, appealing directly to those who supported Nevada rancher Cliven Bundy's armed protest against the federal government in 2014 and a similar, more recent, one staged by Bundy's sons at a federal wildlife refuge in Oregon.
Rubio sought to leverage his local roots in the state -- he lived as a boy with his family in Las Vegas for several years -- as well as reach out to the state's burgeoning Hispanic population, most of which votes Democratic.
For Rubio, considered the Republican establishment's best hope to ward off Trump's insurgency, the Nevada result had to be viewed as somewhat of a setback, following his strong second-place win in South Carolina, the withdrawal of former Florida Governor Jeb Bush from the race, and the bevy of congressional endorsements that came his way as a result.
"If you are Cruz and Rubio you have to worry about how far Trump is getting ahead of you," said Ford O'Connell, a Republican strategist in Washington. "These guys have to figure out how to turn their fire on Trump."
Retired neurosurgeon Ben Carson and Ohio Governor John Kasich, neither of whom had spent much time campaigning in Nevada, lagged behind with single-digit support in early returns.