Last Updated Jan 15, 2016 2:31 PM EST
In the past week, Republican front-runner Donald Trump took a serious scolding from President Obama during the State of the Union address -- as well as from South Carolina's Republican governor, Nikki Haley, during her response to the State of the Union.
Trump has also caused some grumbling among conservatives for needling Ted Cruz over his supposed presidential eligibility questions. Cruz and others, meanwhile, have turned on Trump and his "New York values."
But during Thursday night's presidential debate, Trump showed he's as angry and unapologetic as ever. His approach to the presidential race has clearly paid off in the polls, and it's one he wasn't going to abandon on the debate stage in Charleston, South Carolina, even amid scrutiny.
"I'm very angry," Trump said without any hesitation in the Fox Business debate. "I will gladly accept the mantle of anger."
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His declaration came in response to a question about Haley's official Republican response to the State of the Union, in which she urged members of her own party to resist the temptation to follow the "siren call of the angriest voices." One of those voices, she later said, is Trump.
"When Nikki said it, I wasn't offended," Trump said in the debate. "Our military is a disaster. Our health care is a horror show...we have no borders...Yes, I am angry."
Specifically, Democrats like Mr. Obama and Republicans like Haley -- as well as some of the other 2016 candidates -- have taken issue with Trump's proposal to ban Muslims from the U.S. Is he rethinking his position?
"No," Trump said plainly, keeping up his popular image of a candidate willing to speak his mind, no matter the consequences. "We have to stop with political correctness," he said.
Trump's unapologetic approach at times worked well for him during Thursday's debate -- such as his response to Cruz's criticism of his "New York values." The New York businessman easily brushed off the criticism by invoking the Sept. 11, 2001 terrorist attacks. "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," he said.
At other times, the front runner seemed a little too frank. For instance, he admitted he only honed in on Cruz's eligibility issues "because now he's doing a little bit better" in the polls.
In one of the more lively and prolonged exchanges of the night, Trump insisted he was harping on Cruz's alleged eligibility problem for the good of the GOP.
"Here's the problem," Trump said, explaining the scenario he envisioned unfolding. "I win. I choose [Cruz] as my vice president. The Democrats sue because we cannot take him along for the ride. I don't like that."
Cruz confidently dismissed the issue as a political distraction, remarking, "I've spent my entire life defending the Constitution, I'm not going to be taking legal advice from Donald Trump."
The acrimony on stage, primarily between the two leading candidates, seemed to create a sense of dismay among various candidates at different points of the debate.
Rubio broke up the bickering between Trump and Cruz, remarking, "I hate to interrupt this episode of Court TV... I think we have to get back to what this election has to be about."
Later in the debate, former Florida Gov. Jeb Bush added that, as "wild and woolly" as the nomination process is, "at the end of the day we need to unite behind the winner so we can defeat Hillary Clinton."
Ben Carson similarly chimed in, noting that in the 2012 election, "Republicans tore themselves apart. We have to stop this because, you know, if we manage to damage ourselves, and we lose the next election, and a progressive gets in there and they get two or three Supreme Court picks, this nation is over as we know it. And we've got to look at the big picture here."
While Rubio was primarily focused during the debate on slamming the Obama administration, one of his most forceful moments came in his full-court press against Cruz. The Florida senator aggressively challenged his colleague from Texas on a range of issues, from immigration to crop insurance, portraying Cruz as a politician willing to put his own interests above conservative values.
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"Ted Cruz, you used to say you supported doubling the number of green cards, now you say that you're against it," he said. "You used to support a 500 percent increase in the number of guest workers, now you say that you're against it. You used to support legalizing people that were here illegally, now you say you're against it. You used to say that you were in favor of birthright citizenship, now you say that you are against it."
He continued to rail against Cruz, calling him a flip-flopper. "I saw you on the Senate floor flip your vote on crop insurance because they told you it would help you in Iowa, and last week, we all saw you flip your vote on ethanol in Iowa for the same reason," he said. "That is not consistent conservatism, that is political calculation."
When Cruz insisted he would abolish the IRS, Rubio called him out on it. "You may rename the IRS, but you're not going to abolish the IRS... Someone's going to be collecting this tax," he said, while attacking Cruz's flat tax plan.
Cruz sarcastically thanked Rubio for "dumping your oppo research folder on the debate stage," to which Rubio retorted, "It's your record."