Republicans rally round Romney and the red, white and blue

"We'll put a lot of pressure on Obama, force him to spend time and money in Michigan. That will keep him out of Ohio."

Ohio is, with Florida, one of the most important swing states.

Sometimes self-delusion creeps into Republican rhetoric, as when Schostak tells me that Obama's $80 billion motor industry bailout - which Romney opposed - has disappeared as an issue in Michigan. American-made cars are selling again because of their superior design and quality, not the bailout, Schostak insists.

"People are happy the industry is doing better, but they're not happy that taxpayers' money was used to do it. The government should have used loan guarantees."

Saul Anuzis, the national committee man for Michigan, recalls being the youngest delegate at the 1980 Republican convention, which nominated Ronald Reagan.

"I believe we have the potential to have as important an election as 1980," Anuzis says, asserting that Obama "is the most radical left-wing president we've had in generations".

Republicans compare a Romney victory over Obama to Reagan defeating the incumbent Jimmy Carter. The failed candidate Newt Gingrich and his wife Callista will use their allotted time before the convention to show their documentary on Reagan.

Romney, though, cannot hope to rival Reagan's - or Obama's - charisma. In a USA Today/Gallup poll this week, 54 per cent of voters said Obama was more likeable, to 31 per cent for Romney. The same voters said Obama was more likely to care about them, 52 to 36 per cent.

"It will be a failure of the convention of they don't somehow soften Romney's image," says Kerry Haynie, a political science professor at Duke University. To this end, Romney's wife Ann will tonight tell the convention what a warm and fuzzy guy he is.

A host of Romney acolytes will deliver testimonials to his caring nature before he speaks on Thursday night, including fellow Mormons. Until now, Romney has shied away from publicising his faith. In another shift, he vaunted his record of establishing near universal healthcare as governor of Massachusetts - a legacy from which he hitherto ran away - in an interview with Fox News.

The changes are doubtless prompted by the campaign's internal polling, but the constant shifts blur Romney's image even more. He has often said that Obama is "a nice guy" who "just isn't up to the job".

However, in an interview published yesterday by USA Today, Romney called the president "vituperative" and "vicious", adding, "I do think that the president's campaign of personal vilification and demonisation probably draws some people away from me."

Romney dismissed those Republicans who stress how important it is for him to "connect" with voters in Tampa.

He said the leaders he most admired were Bill Bain, the founder of Bain Capital where Romney made his fortune, and John Willard Marriott, the Mormon founder of the hotel chain, after whom he was named.

If elected, Romney promised, he would treat his cabinet like a board of directors, and apply his management skills to running the country.