NEW YORK — Tensions frayed Monday as Donald Trump tried to stave off the prospect of a lengthy battle to the Republican presidential nomination with a big victory in New York.
In a television interview with Fox News, Trump complained about a ‘‘rigged’’ Republican nomination process. The New York businessman has lost recently-allocated delegates in Colorado to Senator Ted Cruz of Texas.
The comments prompted a fierce defense from party leaders and ridicule from Cruz, Trump’s closest GOP rival.
Campaigning in Southern California, Cruz described Trump’s attacks as ‘‘whining.’’
‘‘Donald has been yelling and screaming. A lot of whining. I’m sure some cursing. And some late-night fevered tweeting,’’ Cruz told hundreds of supporters gathered in Irvine.
He noted that Trump’s complaints follow his struggles in recent primary contests in Utah, North Dakota, Wisconsin, and Colorado.
At a rally in Rochester, N.Y., on Sunday, Trump had blasted the way the country chooses presidential party nominees as ‘‘corrupt’’ and ‘‘crooked’’ — a sentiment echoed by surrogates and supporters who appear increasingly troubled by Cruz’s superior efforts when it comes to wrangling delegates.
‘‘I see it with Bernie [Sanders] too,’’ Trump told Fox News on Monday, pointing to the Democratic race. ‘‘Every time I turn on your show — Bernie wins, Bernie wins, Bernie wins. And yet Bernie’s not winning. I mean, it’s a rigged system folks.’’
Trump’s accusations come as he seeks to outmaneuver Cruz in local state gatherings where the delegates who will attend the summer convention are being chosen.
In state after state, Cruz’s campaign has implemented a more strategic approach to picking up delegates, which, despite Trump’s current lead, are essential if he wants to reach the 1,237 delegates needed to win the nomination.
The complaints call into question the integrity of the voting process at a time when the party could be working to unify behind its front-runner.
In an interview with conservative radio host Mike Gallagher, Reince Priebus, chairman of the Republican National Committee, pushed back against Trump’s claims, saying that the convention system used in Colorado is ‘‘not an affront to the people of Colorado. It just is what the rule is.
‘‘I don’t know why a majority is such a difficult concept for some people to accept,’’ he said.
In a separate development Monday, Trump said only one of his three oldest children will be able to vote for him in next Tuesday’s Republican primary in New York.
New York City voter registration records show that neither Ivanka Trump nor her brother Eric registered with the Republican Party in time to cast their ballots for their father under the state’s arcane voting rules.
‘‘They had a long time to register and they were, you know, unaware of the rules, and they didn’t, they didn’t register in time, so they feel very, very guilty,’’ Trump said in a phone interview with ‘‘Fox and Friends.’’
‘‘But it’s fine. I mean I understand that. I think they have to register a year in advance and they didn’t. So Eric and Ivanka I guess won’t be voting,’’ he said.
While all of Trump’s children have appeared by his side on the campaign trail, Ivanka in particular has played a prominent role, introducing her father at rallies and serving as a key adviser.
She also recorded a series of videos urging her father’s supporters to vote, including one that explained to Iowa voters how to find their caucus sites and how the process worked.
Trump’s eldest son, Donald Jr., is a registered Republican, according to state records. Trump’s youngest daughter, Tiffany, is registered as a Republican in Philadelphia, where she’s a student at the University of Pennsylvania, according to Pennsylvania records. His youngest son, Barron, is 10.
While many states make it easy for voters to participate in their primaries, New York’s voter laws set Oct. 9, 2015, as the enrollment deadline for changing party enrollment in order to participate in the state’s 2016 party primaries, said New York Board of Elections spokesman John Conklin.
That means any voters who wanted to change their party enrollment in time to vote in the presidential primaries would have had to do so by that date.