Last Republicans standing race to grab a slice of Cain's support base

Conservative members of Grand Old Party remain unwilling to settle for Mitt Romney

The "Not Romney" candidates for the Republican presidential nomination are scrambling to win over the former supporters of Herman Cain after the pizza mogul suspended his scandal-hit campaign at the weekend.

With just four weeks left until the first nominating caucuses in the state of Iowa, the party's ultra-conservative wing shows no sign of settling for the establishment favourite, the former Massachusetts Governor Mitt Romney. If anything, his support in Iowa appears to be ebbing, according to a new poll, to the benefit of the former speaker of the House of Representatives, Newt Gingrich, and the libertarian Congressman, Ron Paul.

Meanwhile, the Tea Party's darling Michele Bachmann, Texas Governor Rick Perry and even former Senator Rick Santorum all claimed yesterday that they could consolidate the anti-Romney sentiment in the party and emerge as the challenger to Barack Obama next November.

Mr Cain suspended his presidential run on Saturday, five days after a woman in Georgia claimed to have had a 13-year affair with him. Her allegation was denied by Mr Cain, the former chief executive of the Godfather's Pizza chain. It was the final straw after weeks of revelations that Mr Cain had faced sexual harassment claims from employees while was running a lobby group for the restaurant industry. Until those revelations surfaced, his support in early voting states was high, with conservatives who were suspicious of Mr Romney warming to Mr Cain's unconventional CV and his promise of dramatic tax cuts.

Mr Cain was one of several candidates to have found the party faithful's political core, only to lose support when the media spotlight was trained on them.

Mr Romney has so far failed to break above about 25 per cent in polls of Republican voters because of sustained criticism from the right that he adopted his current conservative positions only recently – after leaving the Governor's office in Boston. Party supporters consistently tell pollsters they fear Mr Romney will immediately tack to the centre on winning the nomination.

Sarah Palin, the former vice-presidential nominee, stoked that concern anew by refusing to accept the contest had become a two-horse race between Mr Romney and Mr Gingrich.

"If voters start kind of shifting gears and decided they want ideological consistency, then they're going to start paying attention to say, Rick Santorum," she told Fox News. Her comments came on the heels of an uncomfortable interview for Mr Romney on Fox, in which he was challenged repeatedly on his changing political positions. Yesterday, Mr Santorum took to ABC television to pitch himself as the next "not Romney". He said: "There is no question Mitt has moved. The question is, what is the sincerity of the move?"

Ms Bachmann, whose campaign appeared to have peaked in the summer, predicted a comeback. "A lot of Herman Cain supporters have been calling our office and they've been coming over to our side," she told CNN.

How the party's backing is split: Latest GOP poll from Iowa

Newt Gingrich 25 per cent
Ron Paul 18 per cent
Mitt Romney 16 per cent
Michele Bachmann 8 per cent
Herman Cain 8 per cent
Rick Perry 6 per cent
Rick Santorum 6 per cent
Jon Huntsman 2 per cent

Source: Des Moines Register