Republican presidential candidate Jeb Bush speaking at a small town hall meeting on 19 August, took a swipe at Republican frontrunner Donald Trump, saying he's not a conservative.

"Mr. Trump has clearly got talent. I mean there's no denying that. He's won over a lot of people. People are very angry about how Washington's not working. He's tapped into that. I respect people that feel the way they do for sure. But when people look at his record it is not a conservative record," the former governor of Florida told the audience in Merrimac, New Hampshire.

"We will never win, we will never win if we are appealing to people's anger each and every day. We will win, we will win when we appeal to their hearts and to their minds and let them believe what I believe to be true. That we truly are on the verge of the greatest time to be alive," he said.

Trump, a real estate mogul who has generated support and controversy with provocative comments on illegal immigration, has rocketed to the top of the polls among a field of 17 Republican presidential candidates.