Ann Coulter. Business Insider Conservative commentator Ann Coulter defended Republican presidential front-runner Donald Trump from a wave of criticism he has endured after failing to correct a questioner who referred to President Barack Obama as a Muslim who was not born in the United States.

In an interview with Business Insider last Friday, Coulter said Trump handled the question like a polished politician. She also speculated that the questioner was a "liberal plant."

"OK, I can’t prove this yet, but I have a huge scoop for Business Insider. … I think that guy was a liberal plant," she said.

Trump had decided to take impromptu questions at a rally in New Hampshire last week, and he did not correct the man who accused Obama of being a Muslim and a foreigner.

Trump instead answered the second part of the man's question about Muslim "training camps" in the US.

"We're going to be looking at a lot of different things, and a lot of people are saying that and saying that bad things are happening out there. We're going to be looking at that and plenty of other things," Trump told the man.

Trump's campaign initially claimed he did not hear the first part of his question, but that did little to quell the controversy. Presidential rivals, the White House, and many political observers criticized Trump, who memorably led a 2011 charge calling on Obama to release his birth certificate.

Regardless, Coulter said politicians on both sides of the aisle are going to have controversial and loud supporters. And she was impressed with how Trump responded to the man in the moment.

"But, either way, I think Trump did it exactly right, and you have to see him do it. I’m kind of surprised he has such good political skills, because obviously a politician is in a tough position," Coulter said.

"There are a certain number of people who support you — I think in either case, not that large a group — and Donald Trump did exactly the right thing. He laughed at the guy. He looked at the crowd and said, ‘First question.’ If you had had an hour to tell Trump what he should do or script it out, it couldn’t have been done better."

Video produced by Graham Flanagan.