When one also considers the frankly weird TV ad of his chief of staff blowing smoke rings, and his inflammatory statements about homosexuality, it is hard to escape the conclusion that Cain, having started off his campaign as a book tour for his autobiography, unexpectedly found himself as front runner and the preferred post-Perry ABM candidate, then had no clue how to capitalise on his success. And that was all before his accusers had alleged sexual harrassment. Even if Cain is completely innocent of all the charges, the memories of the humiliations brought upon the office of the presidency by Bill Clinton's sexual shenanigans would mean that few Americans would want to take a chance on him.

So who else is left standing? Jon Huntsman, who on paper is undoubtedly the best-qualified of all the candidates, poses no threat to Romney because he has cleaved determinedly to the moderate ground, which is more fully occupied by his fellow Mormon. Sometimes it seems that the former Beijing ambassador is anyhow running for the post of Secretary of State rather than President. Huntsman's strategy is risky: it is perfectly possible to win the GOP nomination without the support of the Christian Right — Bob Dole and John McCain both did — but not easy. In private conversation Huntsman is tremendously impressive and likeable, but he resolutely refuses to play to his considerable strengths — he speaks fluent Mandarin, for example — in case he seems too cosmopolitan to the voters in Hicksville, Iowa. (They didn't like John Kerry for being fluent in French, so perhaps he's got a point.) 

It's also worth watching out for the danger of the libertarian Ron Paul standing as a third party candidate. In a three-way poll with Obama and Romney, Paul consistently gets around 18 per cent of the vote, precisely the Ross Perot figure of 1992 and deriving from much the same kind of voters across the political divide. Perot ensured Clinton's victory over the incumbent, George H.W. Bush; if Paul ran as an independent he would hand next year's election to Obama.  

Rick Perry's hopes completely dissolved on the night of November 9 when he announced at a candidates' TV debate that he would abolish three federal agencies, but after mentioning Education and Commerce he could not remember the third. He was given up to a minute to recall its name, but could only say: "Oops", a word that perfectly sums up his entire campaign so far.