A war of words has erupted among the four leading Republican presidential candidates over who is the most conservative, as they engage in ever more frantic attempts to woo the right-wing base of the party.

The hostile attacks on the conservative credentials of the others reflects their efforts to break free from the pack in a race that remains impossible to predict only ten weeks before the first nominating votes are cast.

The latest salvoes came at the Republican Jewish Coalition gathering in Washington yesterday, two days after John McCain called Mitt Romney a conman and 24 hours after Fred Thompson accused the front-runner, Rudy Giuliani, of being a Democrat. The fierce exchanges reflect a deeper debate about the future direction of a troubled Republican Party as it enters the post-Bush era without a clear conservative standard-bearer.

At the Jewish forum Mr McCain, the Arizona senator and a longtime advocate of Mr Bush’s Iraq surge strategy, reminded the audience that he had been to Iraq many times. Then he added: “You’ve got people running for President who have never been there” – a clear reference to Mr Giuliani, who had left the stage minutes before, and Mr Thompson, who was due to speak after him.

Mr Giuliani reminded the audience that when Mayor of New York in 1995, he ejected Yassir Arafat from a concert in the Lincoln Centre. “I didn’t hesitate. I didn’t call for a team of lawyers to tell me what to do,” he said to laughter and applause. Mr Romney, asked at a debate last week if he would bomb Iran without congressional approval, said that as president he would first consult his attorneys. The gibe was the latest in a now openly hostile fight that erupted during the Republican debate last week when Mr Romney and Mr Giuliani challenged each other’s Republican credentials.

On Friday Mr Romney told a crowd that he represented “the Republican wing of the Republican Party”, an effort to appeal to the conservative base and define himself clearly from Mr Giuliani, who is pro-abortion and holds socially liberal views.

This was too much for Mr McCain, who views Mr Romney – the former Massachusetts Governor and a supporter of abortion rights only two years ago – as a cynical opportunist. He noted Mr Romney’s past support for Democrat candidates and his desire, when running for office in Massachusetts in the 1990s, to distance himself from Ronald Reagan.

“You might not agree with me on every issue,” Mr McCain said. “But I hope you know I’m not going to con you.”

Not to be outdone, Mr Thompson made a speech in New York on Monday in which he attacked Mr Giuliani and Mr Romney. He said that it was not time for “philosophical flexibility” – a reference to Mr Romney’s shifts on abortion and other issues. “I am the consistent conservative,” Mr Thompson said.

He later said of Mr Giuliani: “I don’t think the mayor has ever claimed to be a conservative.”

Tucker Eskew, a Republican strategist, said: “The Republicans are a party in transition.

“We are entering the postBush era. We are figuring out what it means to be a Republican.”

Fighting funds

Candidates’ funds at close of third quarter on September 30

Hillary Clinton $50.4m

Barack Obama $36m

John Edwards $12.3m

Rudy Giuliani $16.6m

Mitt Romney $9.2m

Fred Thompson $7.1m

John McCain $3.4m

Mike Huckabee $651,000

Source: Federal Election Commission

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