The gloves were fully off in the first GOP debate of 2016

Marco Rubio, Donald Trump and Ted Cruz during the Fox debate. Photo: Getty Images

Coming into Thursday night’s Republican presidential debate, all signs pointed to a debate in which tensions might boil over.

The candidates didn’t disappoint.

The seven Republican candidates on stage for the first GOP debate of 2016 produced clash after clash, as the voting in the early-primary states gets ever closer.

The debate started off rather slowly. That changed when Fox Business moderator Neil Cavuto asked Sen. Ted Cruz (R-Texas) about the questions surrounding his eligibility to run for president.

Trump has brought up questions about Cruz’s eligibility to run for president on a recurring basis in recent weeks, as Cruz has surged in polls of the first-caucus state of Iowa.

Cruz accused “my friend Donald” of only questioning his eligibility for president because of that fact — and because the real-estate mogul’s poll numbers have been sinking.

“Back in September, my friend Donald said he had his lawyer look at this from every which way and there was no issue there. There was nothing to this ‘birther’ issue. Since September, the Constitution hasn’t changed. But the poll numbers have,” Cruz said to whistles and cheers from the crowd.

“And I recognise that Donald is dismayed that his poll numbers are falling in Iowa,” he added. “But the facts and the law here are really quite clear.”

Trump responded by touting his poll numbers. But he was booed while citing a new NBC News/Wall Street Journal poll, published earlier on Thursday, that gave him a 13-point national lead over Cruz. The businessman claimed that the crowd was booing Cruz, not him.

“You have a big lawsuit over your head while you’re running. And if you become the nominee, who the hell knows if you can even serve in office,” Trump said.

They weren’t done.

Later, the two sparred over Cruz’s recent repeated declaration that Trump exhibits “New York values.”

Cruz has suggested voters in Iowa should consider the real-estate mogul’s hometown in recent days. Fox Business anchor Maria Bartiromo asked Cruz to explain what he meant by the term “New York values.” Cruz initially declined to elaborate.

Cruz eventually praised “many wonderful, wonderful working men and women in the state of New York, but everyone understands that the values in New York City are socially liberal, are pro-abortion, are pro-gay-marriage, focused around money and the media.”

“I guess I can frame it another way: ‘Not a lot of conservatives come out of Manhattan,'” Cruz quipped later. “I’m just saying.”

Trump then fired back at Cruz.

“Conservatives do actually come out of Manhattan,” the Queens-born businessman explained, citing William F. Buckley, Jr., the founder of the conservative magazine National Review.

As he did earlier this week, Trump said “New York values” could be seen in how the city came together and rebuilt itself after the September 11, 2001, terror attacks.

“He insulted a lot of people,” Trump said of Cruz. “When the World Trade Center came down, I saw something that no place on earth could have handled more beautifully, more humanely than New York.”

But Trump and Cruz didn’t provide the only fireworks of the night.

Toward the end, of the debate, Sen. Marco Rubio (R-Florida) and Cruz aired out a fight that has long been brewing on the campaign trail.

Bartiromo noted that the US is on track to issue more green cards and asked why Rubio was allegedly supporting opening borders to foreign workers when Americans are having a hard-enough time getting jobs.

This opened up a prolonged back-and-forth of attacks between Rubio and Cruz.

Rubio accused Cruz of flip-flopping on certain key positions, namely immigration and defence spending, and listed a litany of issues about which Cruz has supposedly changed his mind.

“That is not consistent conservatism,” Rubio said. “That is political calculation.”

Cruz demanded time to respond to what he said were at least “11 attacks” from Rubio. He told Rubio, “I appreciate you dumping your oppo research folder.”

“At least half of the things Marco said are flat-out false,” Cruz said. “They’re absolutely false.”

On immigration, Cruz said that Rubio stood with Sen. Chuck Schumer (D-New York) and President Barack Obama.

Christie RubioScreenshot/FoxNew Jersey Gov. Chris Christie and Florida Sen. Marco Rubio at the Fox Republican debate on Tuesday, January 14.

Meanwhile, New Jersey Gov. Chris Christie (R) and Rubio also duked it out on stage.

Cavuto, the moderator, pointed out that Rubio and Christie had “exchanged some fairly nasty words” recently.

He was referring to Christie saying that Rubio can’t “slime [his] way to the White House,” in response to ads Rubio ran suggesting that Christie agrees with President Barack Obama too much on certain issues like the Common Core education standards and gun control.

Cavuto asked Rubio if he went too far and if he wanted to apologise.

Rubio didn’t apologise and accused Christie of supporting gun control, Planned Parenthood, and the controversial educational standards that make up the Common Core.

“All I’m saying is that our next president cannot be someone that does the damage that Barack Obama does to this country,” Rubio said. “It cannot be someone that continues his agenda.”

Rubio warned that if US voters don’t “get this election right,” then there might be “no turning back for America.”

Christie responded by saying he stood onstage watching Rubio “rather indignantly” tell former Florida Gov. Jeb Bush (R) that “someone told you that because we’re running for the same office, that criticising me will get you to that office.”

Before defending his record, he then shot at Rubio: “It appears that the same someone’s been whispering in ol’ Marco’s ear, too.”

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