IF Mike Huckabee is a shadow of his former self, it is not because of the rigours of the 2008 presidential campaign. The Republican candidate is fighting fit after shedding 110lb and rising regularly at 4.30am for marathon training.

Named by Time magazine as one of the five best governors in America for his stewardship of Arkansas, Huckabee has often been cited as a dark horse for the Republican nomination. But the amiable ex-governor – slogan, “I like Mike” – is finding it hard to leave the starting gate in a race ruled by candidates with the biggest names and fattest purses.

His struggling candidacy reveals the extent to which the Republican party is in a self-destructive funk. Instead of congratulating themselves on the breadth and depth of their field, from the war hero John McCain and the crime-busting Rudy Giuliani to successful governors such as Mitt Romney and Huckabee, activists seem determined to rubbish their own candidates before the Democrats have the chance to finish them off.

“It is intensely frustrating,” Huckabee said on the campaign trail in Iowa. “They think the meat that is going to be put on the counter tomorrow will be fresher than today’s, even if it won’t be for long.”

He was clearly referring to Fred Thompson, the former senator for Tennessee and star of the TV series Law and Order, who has become the darling of social conservatives without declaring his candidacy. His looming presence is stalling the race for the Republican nomination and allowing dissatisfaction to fester with little evidence he will be the party’s longed-for saviour.

Huckabee fears that, by default, the Republicans will hand victory to Hillary Clinton, the Democratic frontrunner whom he first came to know as the first lady of Arkansas. It could usher in an age of dynasty, he warned, which would be against America’s founding spirit.

“If Clinton wins the next election, we will have 24 years of the presidency divided between two families,” Huckabee grimaced. “At that point we might as well adopt your model of royalty and trade it between a Democratic and Republican monarch.”

By British standards Huckabee is something of a political oddity. The 51-year-old topped the scales at more than 280lb when he was diagnosed with diabetes. His doctor warned he would die in 10 years if he failed to diet and exercise. The self-described “foodaholic” went on to shed weight so rapidly that he was said to have unzipped his fat suit and stepped out a slim man.

Devouring hamburgers and ice-cream sundaes at diners while campaigning has become a compulsory way to commune with middle America. “I have to be really careful,” said Huckabee, who still misses his favourite fried chicken. “I carry protein bars and peanuts with me and if you really work at it you can find a salad or chicken wrap.”

A former Baptist preacher, he was one of three candidates in a recent Republican debate to disown evolution, raising guffaws among America’s liberal elite. “I believe the work of God is not a biological accident. How did He go about it? Dunno, I wasn’t there,” Huckabee said. “If someone wants to look up their family tree and find primates, that’s their business. I choose not to.” Far from disqualifying him from office, his views are in tune with those of many voters. A recent Newsweek poll found that only 13% of Americans believed evolution best explained human development, while 78% thought there was at least some form of divine guidance.

Huckabee performed so well in the debate that the conservative commentator John Podhoretz exclaimed half way through that he was “really terrific. It’s hard to know whether a debate watched by only a few million people can really launch someone but I’d say he is far and away the most likeable and eloquent candidate on that stage”.

This Tuesday the Republican caravan moves on to South Carolina, a Bible Belt state that is hosting the next 2008 debate. Huckabee is hoping to shine there after coming second in a straw poll to Mitt Romney, who is favoured by social conservatives but is trying their patience with a long list of flip-flops over issues such as abortion.

An exasperated Giuliani last week gave up trying to appease the Republican base on abortion and came out firmly pro-choice. The pro-life Huckabee, meanwhile, is seizing the opportunity to present himself as an “authentic” conservative who is also compassionate to the disadvantaged, such as single mothers and the unemployed. “I don’t hold my positions out of political convenience,” he said.

He believes in keeping troops in Iraq to prevent “mass genocide” but would like to drop the George Bush swagger. “When a superpower flaunts its status it creates resentment. The ‘you’re either with us or against us’ approach leads others to say, ‘Wait a minute, we’re a sovereign nation too and nobody is going to put us down like that’.”

In a field in which every candidate has a seemingly fatal flaw, Huckabee’s might be that he is from a town called Hope, like Bill Clinton. The former governor’s greatest problem, though, is money. He raised only $500,000 in the first three months of the campaign.

In Iowa, speaking to the Association of Bandmasters, he won over the audience with his passion for music – he plays bass guitar in a rock band, Capitol Offense. “He was absolutely spectacular,” said Doug Robinson, a Republican activist.

Robinson added: “There are a lot of great candidates. I like him and I like Mitt Romney.” Then he sighed: “But I don’t know who is dynamic enough.”

The problem is not the quality of the candidates, it is the party’s lack of confidence.

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