Just 622 days to go and the US presidential election campaign is entering its final frenzy of activity. With the race entering the home stretch, the field has narrowed to the last 117 candidates and they are desperately striving, as the clock ticks down the last 21 months, to convince the dwindling number of undecided voters that they should be the next President.

The big story this week was on the Democratic side where Hillary Clinton, whose political skin is about as sensitive these days as Britney Spears’s cranium, got into an ugly fight with Barack Obama, the saintly new man of American politics.

It all involved, as it nearly always does in Democratic politics, hurt feelings over the shifting affections of Hollywood moguls. David Geffen, of Spielberg-Katzenberg-Geffen Dreamworks fame, held a $1.3 million fundraiser in Los Angeles for Mr Obama this week, and while he was at it said some unpalatable (read: true) things about the Clintons.

“Everybody in politics lies,” he told Maureen Dowd, the New York Times columnist, “but they [the Clintons] do it with such ease it’s troubling.”

This constitutes a high tackle in anyone’s game book but what made it much worse is that Mr Geffen used to be a Clinton man. He forked out millions of dollars for the First Family during the Bill Clinton presidency when that was the going rate for a night of fun in the Lincoln bedroom at the White House (of course, if you were female, 22 years old and in the habit of displaying a thong above your outer garments, deep discounts were available).

Mrs Clinton said Mr Geffen’s remarks were outrageous and called on Mr Obama to return Mr Geffen’s tainted 1.3 million pieces of silver.

Shan’t, said Mr Obama, and anyway you’ve consorted with some people who’ve said nasty things about me. And on it goes.

On the Republican side, things were simmering nicely as Mitt Romney, the former Massachusetts Governor, also got into a bit of trouble. He attacked other candidates for their not very conservative views on social issues such as abortion but then had to own up to some extraordinary gyrations of his own on the subject. By his admission, it now looks as though he was against abortion, then he was for it, then he was against it again and now he’s for it (I do not exaggerate).

And Dick Cheney, the Vice-President, ever eager to reinforce his reputation as the final repository of lost causes, clashed with Senator John McCain, another leading Republican candidate, over the latter’s observation this week that Donald Rumsfeld was “one of the worst secretaries of defence in history”.

“I think Don’s a great secretary,” Mr Cheney told ABC News, in a curious use of the present tense that only augmented the sense that he lives in his own slightly delusional universe, and went on to suggest that Mr McCain ought to apologise to Mr Rumsfeld.

They’re not going to be able to keep this up. If it goes on like this for another 20 months American presidential politics is going to resemble one of those barroom scenes in a Western where no one is left standing except for the little old dipso in the corner blissfully unaware of the carnage going on around him.

The ridiculously early start to the 2008 presidential election could create an entirely new dynamic all of its own. It is quite possible that by the autumn, when the campaign would normally be starting, and when there will still be four months to go before the first votes are cast in the two parties’ primary elections, that voters will be thoroughly turned off. Even if they haven’t succeeded in making each other look like the devil, the candidates run the risk of simply boring everybody senseless.

As Newt Gingrich, the former Republican Speaker of the House of Representatives, who has perhaps shrewdly opted to sit this out until the autumn, said this week, it will be like one of those television reality shows where the viewers will want to vote everybody off.

This could just be the germ of an idea. Since American Idol, the musical talent show, is the most successful programme in television history, watched by tens of millions of people every night, perhaps a more useful way of winnowing the presidential field would be to have them stand up and perform in front of Simon Cowell, who could offer withering assessments of their efforts: “Did you say you were the grandson of a Kenyan goat herder, Mr Obama? I think you might want to get back into the family business.”

Furthermore, since the primary elections, in which the two main parties select their presidential candidates, are now to be bunched into a short period early next year, it means that by early February 2008, we will know who those candidates will be and will face — at nine months — the longest general election campaign in history.

All this raises two intriguing possibilities. First, one of the handful of American-born citizens over the age of 35 who is not a candidate for President at the moment could emerge from nowhere as a contender in the late stages of the blood-spattered primaries.

Who could this be? On the Republican side, clearly Mr Gingrich himself is a potential contender, though, even on the sidelines he remains a divisive figure in American politics, after a bruising decade with the Clintons.

On the Democratic side, much attention will focus on Al Gore, the former Vice-President. But I doubt that he will want to risk his Oscar and Nobel-prize-winning purity by diving once again into the mucky pool of presidential politics.

More likely is that one of the current second-tier candidates in the Democratic race — Bill Richardson, the former Governor of New Mexico, pictured, for example, or even Tom Vilsack, the former Governor of Iowa, will get catapaulted into the front ranks.

The second possibility is that, as the long general election next year bores and alienates more voters there must be a similar chance of a third-party candidate emerging to take on the designated Democrat and Republican — as Ross Perot did in 1992, and again, less successfully in 1996.

Step forward, President Donald Trump?

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