This is an archived article that was published on sltrib.com in 2016, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

North Charleston, S.C. • Ending months of civility, Republican presidential candidates Donald Trump and Ted Cruz clashed in fiery disagreement Thursday night over polls, values and even the Texas senator's eligibility to serve as commander in chief. The billionaire businessman declared the eligibility issue could put the GOP at risk of a disastrous loss to Democrats.

"There is a big question mark on your head," Trump told Cruz, who was born in Canada to an American mother. "You can't do that to the party."

It was one of many heated exchanges between a pair of candidates seeking to tap into support from voters who are angry and frustrated with Republican Party leaders as well as Democrats.

Cruz renewed his criticism of "New York values," a coded questioning of Trump's conservatism that elicited an unexpectedly emotional response from the real estate mogul about his hometown's response to the Sept. 11, 2001, attacks.

"No place on earth could have handled that more beautifully, more humanely than New York," Trump said. "That was a very insulting statement that Ted made."

The exchanges signaled an end to months of relative friendliness between Trump and Cruz. While Trump has led the GOP race for months, the Texas senator is on the rise in Iowa, where the Feb. 1 caucuses kick off voting in less than three weeks.

At times, the contest between some of the more mainstream candidates seeking to emerge as an alternative to Trump and Cruz was just as fiery, particularly between Florida Sen. Marco Rubio and New Jersey Gov. Chris Christie.

Rubio likened Christie's policies to President Barack Obama's, particularly on guns, Planned Parenthood and education reform — an attack Christie declared false. Seeking to undermine Rubio's qualifications for president, Christie suggested that senators "talk and talk and talk" while governors such as himself are "held accountable for everything you do."

Still, Trump and Cruz dominated much of the prime-time debate, the first of the new year.

Cruz accused Trump of raising questions about his citizenship simply as a response to his stronger standing in the polls that Trump still frequently touts in campaign events. The senator was also on the defensive about his failed disclosure on federal election forms of some $1 million in loans from Wall Street banks during his 2012 Senate campaign, saying it was little more than a "paperwork error."

Thursday night's debate came at the end of a week that has highlighted anew the deep rifts in the Republican Party. South Carolina Gov. Nikki Haley, a rising GOP star, was widely praised by many party leaders for including a veiled criticism of Trump's angry rhetoric during her response to Obama's State of the Union address — only to be chastised by conservative commentators and others for the exact same comment.

Trump said he wasn't offended by Haley's speech and argued his anger is justified.

"I'm very angry because our country is being run horribly," he said. "And I will gladly accept the mantle of anger."

Trump also stuck with his controversial call for temporarily banning Muslims from the United States because of fear of terrorism emanating from abroad. He said he had no regrets about the proposal and noted his poll numbers rose after he announced the plan.

Former Florida Gov. Jeb Bush, who has emerged as a frequent critic of Trump, urged the front-runner to reconsider the policy.

"What kind of signal does that send to the rest of the world?" said Bush, who has struggled to gain any momentum in the race and often appeared overshadowed Thursday night.

On the economy and national security, the candidates offered a sharp contrast to the optimistic portrait of the nation Obama outlined in his State of the Union address and warned that sticking with Democrats in the November election could have dire consequences.

"On Tuesday night, I watched story time with Barack Obama, and it sounds like everything in the world was going amazing," Christie said.

Cruz accused Obama of painting a rosy picture of the country's economic situation while working Americans are being "left behind," and said Democratic front-runner Hillary Clinton would continue the same policies. Bush suggested the country was less safe under Obama and declared Clinton would be a "national security disaster."

Rubio went even further, saying Clinton was "disqualified for being commander in chief," accusing her of mishandling classified information and lying to the families of Americans killed in the 2012 attacks in Benghazi, Libya.