US Republicans, who once steered a steady course to power by extolling Christian conservative values, now find themselves adrift in a sea of doubt and buffeted by waves of scandal.

The two early front-runners for the party’s 2008 presidential nomination, John McCain and Rudy Giuliani, have seen support steadily erode as right-wing rivals Mitt Romney and Fred Thompson climb up the opinion polls.

Mr McCain has suffered worst, with support now lagging in single digits according to some surveys. A dismal week got worse yesterday when two strategists quit his campaign in Iowa and it was revealed that Bob Allen, the co-chairman of his Florida campaign, was arrested after allegedly offering to perform a sexual act for $20 (£10) on an undercover policeman.

His two most senior campaign aides, Terry Nelson and John Weaver, resigned abruptly this week. And his chief of staff, Mark Salter, sidelined himself amid suggestions that Mr McCain’s top-heavy campaign was almost penniless, with debts wiping out most of his remaining $2 million.

The British Government, which compiles regular assessments on the 2008 race, is coming close to writing off Mr McCain’s slender chances.

The departure of Mr Weaver is being described by the Foreign Office as “akin to Karl Rove walking out on Bush”. The Arizona senator, who sought to portray himself this year as the Establishment Republican and tied himself to President Bush’s Iraq war strategy, has struggled to win support from conservatives. Their long-standing suspicions appear to have been confirmed by his alliance with the liberal Democratic Senator Edward Kennedy on an immigration Bill that would give undocumented workers a pathway to US citizenship.

Mr Giuliani is also struggling to convince the “values voters” who dominate the Republican base. The thrice-married former Mayor of New York, who has supported gay and abortion rights, has lost Thomas Ravenel, his South Carolina campaign manager, who faces charges of being a cocaine dealer. This week Senator David Vit-ter, the chairman of his campaign in the southern states, confessed to a “very serious sin” after his phone number showed up in the records of an escort service.

Mr Giuliani has maintained a narrowing lead in the Republican contest partly because of his strong national security credentials as “America’s mayor” after the 9/11 attacks. But the International Association of Fire Fighters has produced a 13-minute video, Rudy Giuliani: Urban Legend, that lambasts his leadership of New York after the terror attacks in which nearly 350 of their colleagues died.

The most likely beneficiary is Mr Thompson – a former senator and actor – who has assiduously courted values voters. But even before he announces his candidacy formally, Mr Thompson’s conservative credentials are being questioned by claims that in 1991 he accepted a lobbying job pushing for the right of family planning clinics to offer advice on abortions.

Meanwhile, Mr Romney is still seeking to overcome prejudice against his Mormon faith and suspicions over his belated conservative conversion on social issues such as abortion. In recent weeks he has also fallen foul of animal rights campaigners after admitting that he used to strap his dog on to the roof rack for long road trips.

Frank Luntz, a Republican pollster, said that, collectively, “these guys are in real trouble”. Democratic candidates have raised $146 million this year, compared with the Republicans’ total of $93 million. Mr McCain, he added, had suffered “a whole campaign meltdown” in a matter of days.

Instead, the contest was now becoming a three-way race between Mr Romney, Mr Giuliani and Mr Thompson. Mr Romney is pursuing a strategy to win the early-voting states of Iowa and New Hampshire.

Mr Giuliani, by contrast, is running a national campaign unworried by Iowa and New Hampshire. He is the only candidate with the money recognition to wrap up a huge number of delegates on the big voting dates, Mr Luntz said.

Presidential promise

John McCain flew as a naval bomber pilot and served in Vietnam after graduating from the US Naval Academy in 1958. His father and grandfather had also served in the US Navy

He was shot down in 1967 and spent the rest of the war as a prisoner of the North Vietnamese, much of it in solitary confinement

In 1980 Mr McCain divorced his first wife, Carol. A month later he married Cindy, his current wife

He was elected to Congress in 1982 to represent what was then the first congressional district of Arizona

He joined the Senate in 1986, replacing Barry Goldwater as senator for Arizona. He is currently Arizona’s senior senator

Mr McCain made an unsuccessful bid for the Republican presidential nomination in 2000

Sources: Times archives; www.mccain.senate.gov; www.johnmccain.com

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