Columbia, South Carolina (CNN) Donald Trump acknowledged Thursday that he "could have" signaled support for invading Iraq during a 2002 interview with Howard Stern.

"It was probably the first time I was asked that question," the GOP presidential front-runner told CNN's Anderson Cooper during a South Carolina town hall. "By the time the war started, I was against the war."

He also noted he "wasn't a politician" at the time of the interview.

Ahead of Saturday's South Carolina Republican primary, Trump has repeatedly blasted former President George W. Bush for launching the war.

But Buzzfeed posted Thursday Trump's interview with Stern, given on the first anniversary following the Sept. 11, 2001, terror attacks. When asked whether he would support an invasion, Trump responded: "Yeah, I guess so."

"You know, I wish the first time it was done correctly," he added in the interview.

Trump's criticism of the war could be a risky move in this military-dominated state. One man in the audience confronted Trump for saying that Bush had lied about the existence of weapons of mass destruction in Iraq.

"I would probably say that something was going on," Trump said. "I don't know why he went in" to Iraq.

Trump vs. Pope Francis

Trump called Pope Francis a "wonderful guy" after the pontiff said Thursday the candidate is "not Christian" if he wants to deport undocumented immigrants and build a wall along the U.S.-Mexico border.

"I don't think this is a fight," Trump said. "I think he said something much softer than was originally reported by the media."

Trump added he would meet with the Pope "anytime he wants."

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Earlier at the town hall, Jeb Bush and John Kasich refused to be drawn into the debate between Trump and the Pope.

Kasich simply said he was "pro-Pope."

"This man has brought more sense of hope and more about the do's in life than the don'ts," Kasich said, referring to the Pope. "This guy has been so humble."

Bush, who is a devout Catholic, didn't criticize the Pope's comments. But he said he personally wouldn't "question people's Christianity."

"I think that's a relationship they have with their Lord and savior and themselves. So I just don't think it's appropriate to question Donald Trump's faith," Bush said. "He knows what his faith is."

Dominating South Carolina

Trump, who is dominating most South Carolina polls, continued to pound his closest competitor: Ted Cruz.

The billionaire businessman said the Texas senator "has a problem with the truth."

Trump appeared to side with Marco Rubio after the Florida senator's campaign accused Cruz's team earlier Thursday of photoshopping an image to make it appear as though Rubio is shaking hands with President Barack Obama.

"Oh, it was totally photoshopped," Trump said.

"They even made Marco a lot shorter than he is," Trump said, adding that this was "probably the thing that bothered him the most."

He quipped that other tactics the Cruz campaign has used in this election were "disgusting."

Trump has confounded many political observers with his propensity for colorful, unfiltered and inflammatory language as a candidate. When Cooper asked whether he would take on a different tone as president, Trump suggested he could easily switch back and forth between being politically correct -- and not.

"I can be more politically correct than anybody you've ever interviewed," Trump said.

He added: "I can do whatever I want. ...I deal with society. Society loves me."

Trump also shed light on his habits on the road, including his propensity to consume fast food from big chains like McDonald's and Burger King.

"I'm a very clean person. I like cleanliness," he said. "And I think you're better off going there than maybe some place where you have no idea where the food is coming from."

He said he recently ate Kentucky Fried Chicken. His verdict: "Not the worst thing in the world."

John Kasich

Kasich opened the CNN event by reflecting on a campaign trail moment that's quickly gone viral. At a forum in Clemson earlier in the day, a tearful young man confessed to Kasich that after suffering personal losses, he had gone through a very dark period in life. Now, he had found hope in the message that Kasich was taking to voters, he said, prompting the governor to hug the man.

"There are a lot of people out there who are lonely," Kasich told Cooper. "Could you believe that young man?"

He expressed frustration with the frenetic pace of presidential politics and noted how important it is to "slow down" and listen to people in need.

JUST WATCHED Kasich: Be present for others' wins and losses Replay More Videos ... MUST WATCH Kasich: Be present for others' wins and losses 01:36

"We've got to slow down," Kasich told Cooper. "You've got to celebrate other people's wins, and sometimes you've got to sit with them and cry."

Kasich is coming off a strong second-place showing in New Hampshire last week, but with his moderate message, there is little expectation that he will have a strong performance here during Saturday's GOP primary.

When one woman in the audience asked whether he would consider appointing any of his fellow White House hopefuls to his Cabinet, Kasich lightheartedly reminded her that it was much too early in the race.

"Well, look. I'm not going to be measuring like, the drapes. I've got a long way to go. We're really, really early," Kasich said.

He did, however, call one former candidate a "terrific guy" whom he would consider appointing to his administration: New Jersey Gov. Chris Christie.

"I like him very much," Kasich said, before saying about the rest of the field: "They all deserve an awful lot of respect. I don't want to fight with them."

JUST WATCHED Kasich: Losing parents to drunk driver changed my life Replay More Videos ... MUST WATCH Kasich: Losing parents to drunk driver changed my life 01:05

At the conclusion of his time at the CNN event, Kasich opened up about how losing his parents in a car accident forever shaped his outlook on life.

"They were at the Burger King because they got the second cup of coffee for free. That's the way the mailman and Mrs. Kasich lived," Kasich said about the day his parents died. "I went into a black hole."

He soon found God, Kasich said, though "the pain still comes."

"As a result of my parents' accident, it's allowed me to hug that boy," he added.

Jeb Bush

Bush shrugged off South Carolina Gov. Nikki Haley's decision this week to endorse Rubio.

"I'm marking her down as neutral," Bush quipped.

Pressed by Cooper on how he can still convince voters here that he has momentum, Bush insisted that the momentum is there.

"I do have momentum if you look at the polls and if you look at the crowd sizes of our town hall meetings," Bush said. He pointed to the endorsement he won from South Carolina Sen. Lindsey Graham as a sign of his readiness to be president.

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"He could have supported two of his colleagues, Ted Cruz and Marco Rubio," Bush said. "He chose me because he believes that I would be ready to serve on day one as commander in chief and as leader of the free world."

A University of South Carolina student told Bush that it seemed to him marijuana was one of the most frequently used drugs on campus, and asked the ex-governor for his stance on legalization.

Bush said he took issue with the term "recreational drug."

"The terminology is probably a little misleading," Bush said, "because of the potency of this generation of marijuana. It has major impacts -- neurological impacts."

He briefly mentioned his daughter's struggles with addiction, and said he believes the government should "focus a little bit more on treatment and a little less on punishment" of individuals convicted on drug-related charges.

One of the more personally revealing moments for Bush came when a questioner asked him to describe how his wife, Columba, has shaped him as a leader. Bush turned to his wife, who was sitting in the audience next to former first lady Barbara Bush, and said, "Sweetie, this is going to be your anniversary present."

He recalled meeting his wife as a young man in Mexico.

"Five o'clock. I can remember exactly where I was on the town square. I can remember exactly what she looked like to this day," Bush said.

The experience of falling for Columba -- "the most beautiful girl I had ever met in my life" -- Bush said, was like being hit with a "lightning bolt."