Donald Trump, the property developer and reality TV powerhouse who insists he may run for the Republican nomination for the White House next year, is on a roll.

Polls now put him in second place in the race to secure the Republican nomination and not even his local paper, which yesterday Photoshopped him to look like a clown, can slow his momentum.

Dismissing "the Donald" as a contender has become more difficult, even if he seems preoccupied by the so-called "birther" conspiracy that says President Barack Obama was not born in Hawaii.

A recent Wall Street Journal poll of possible Republican runners showed him tied in second place with Mike Huckabee and only four points behind Mitt Romney.

Even the White House is training its guns on him. "There's zero chance that Donald Trump would ever be hired by the American people to do this job," said David Plouffe, Obama's senior political adviser.

The tycoon has also got the attention of the New York Times, which published a letter in which he attacks columnist, Gail Collins, for lambasting him over the birth certificate issue. "I have great respect for Ms Collins in that she has survived so long with so little talent," he wrote.

Among those taking issue with Trump on Obama's eligibility is "If [he] worked for us, we'd have to say: 'Donald, you're fired - for incompetence.' When it comes to getting facts straight, he fouls up."

Former Massachusetts Governor Romney yesterday became the second prominent Republican after Minnesota's Tim Pawlenty to challenge Obama, declaring he would "put America back on a course of greatness."

- Independent, AP