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Rudy Giuliani’s first television advertisement hits screens across New Hampshire today, amid warnings that he has miscalculated by focusing too hard on the big states holding presidential primary elections later next year.

Although he remains the front-runner for the 2008 Republican nomination, a series of recent polls suggest that he faces defeat in all three of the states that kick off the nominating process in January.

Critics say that Mr Giuliani’s strategy of bypassing the small, but often contrary, early states has risked giving his opponents a head start – or even unstoppable momentum. His support languishes at about 13 per cent in Iowa, behind Mitt Romney and the rapidly rising Mike Huckabee. In Michigan - where Mr Romney’s father was a popular governor – Mr Giuliani is in second place, while in New Hampshire he is tied with John McCain for the runner-up spot.

In a fourth early state, South Carolina, he is in a three-way fight with Mr Romney and Fred Thompson. But Dick Morris, a political strategist for both Republicans and Democrats, predicted that Mr Giuliani would “get creamed” there too “if he loses the first three contests”.

He added: “Rudy has brought this crisis on himself by foolishly running no television ads in any of the early primary or caucus states, while Romney has advertised for six to eight months [and] may have built up an insurmountable lead in the interim.” Mike DuHaime, the Giuliani campaign manager, insists he is confident that the former Mayor of New York would still win delegate-rich Florida – where he has a strong lead in the polls – even after such early setbacks.

“This is not necessarily the traditional way,” he said. “Conventional wisdom has never guided this campaign.” His theory is that whatever happens in the first few states, Mr Giuliani can win Florida on January 29 and then kick on to “Super Tuesday” on February 5 when a new foreshortened electoral calendar will see a host of populous states voting.

Advisers say that his northeastern connections make him favourite to take New York, New Jersey and Connecticut, while polls also suggest he is well placed to win California – the biggest prize of all.

Mr Giuliani is the last top-tier Republican candidate to begin TV adverts, reflecting a strategy of keeping his money in reserve for the bigger states. But his supporters say that the decision to screen advertisements in New Hampshire is “not a panic move”, saying “it should be seen as a sign that we can win there as well”. Mr Romney told an interviewer this week that by concentrating his efforts in the early states, “I’m just following the same path that every nominee for president has followed in the past”.

He predicted that his rivals were going to start “shooting rockets off in my direction” across the early states, saying: “It’s going to get very narrow. I’m going to be facing stiff competition from one or more of the candidates.”

Yesterday there were reports of divisions within Mr Romney’s campaign over how far it should make negative attacks on Mr Giuliani who has a chequered personal life, tainted associates, such as the indicted former New York police chief Bernie Kerik, and a record of social liberalism with is anathema for many Republicans.

Some strategists caution of a “murder-suicide” scenario, in which Mr Romney might draw blood from Mr Giuliani but also kill his own chances if voters are alienated by such attacks.

Democratic candidates, who face each other tonight in a televised debate at Las Vegas, are also pouring resources into the early states.

Hillary Clinton has seen her lead in Iowa slip to 2 per cent in recent polls, while also seeing her margin in New Hampshire trimmed to a still commanding average of 13 per cent.

David Plouffe, Barack Obama’s campaign manager, said: “There are growing signs in the last ten days that Clinton’s support in the early states, as well as nationally, is fairly thin and eroding.”

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