Former President Donald J. Trump glided to victory in Nevada’s Republican caucuses on Thursday, an outcome all but guaranteed because he was the only major candidate on the ballot.

The Associated Press declared Mr. Trump the winner shortly after caucus sites closed in Nevada, giving him his fourth straight triumph in a Republican nominating contest that awards delegates this year.

Even in a campaign in which Mr. Trump’s dominance has sapped the race of much of its drama, his win in Nevada felt particularly preordained. His last significant G.O.P. rival, Nikki Haley, opted months ago to skip the caucuses, which were run by the Nevada Republican Party, and participated instead in a primary election on Tuesday required by state law.

Ms. Haley still won the contest, but its results were effectively immaterial. The state’s Republican Party, which is led by a close Trump ally, decided that it would allocate its presidential delegates based only on the caucuses, and it forced candidates to choose to participate in one contest or the other.

The symbolic success by Mr. Trump on Tuesday was part of a strategy pushed by his supporters in Nevada, including its Republican governor, and offered further indication of the former president’s hold among Republicans in the state.

Competitive or not, Mr. Trump’s victory in the caucuses on Thursday remains a crucial prize that allows him to rack up delegates and claim additional momentum as attention shifts to South Carolina’s primary, his next battle with Ms. Haley, on Feb. 24.

His win also capped off a remarkable day on the trail that started with the Supreme Court signaling it was likely to overturn a ruling that had removed Mr. Trump from Colorado’s presidential ballot.

His campaign will likely also be bolstered by a special counsel’s report that raised pointed questions about President Biden’s mental acuity and which Mr. Trump has already cited as he continues to argue that the criminal charges he faces are politically motivated.

The former president also won the U.S. Virgin Islands caucuses on Thursday, capturing 73 percent of the vote.