Can it really be almost 16 months until it is finally over? It feels like it has lasted that long already. The vast army of American psychiatrists must be rubbing their hands in anticipation of the extra fees as distressed voters seek out their services. It will not be January until anyone is formally consulted on who should be the next President of the United States, but the media are treating the whole affair as if the Iowa caucus were tomorrow and the New Hampshire primary on Thursday.

There seems to be a new opinion poll every week, even though great numbers of electors have never heard of some of the more prominent contenders, never mind the obscure ones. The battle next year for the White House will be the longest, most expensive and maddest in history.

Why the longest? Mostly because the race is so unusual. In every election since 1952 there has either been an incumbent President or serving Vice-President on the ballot paper. A sitting President is normally renominated either unopposed or after token opposition. When a Vice-President seeks his party’s backing he usually gets it, as did Richard Nixon, Hubert Humphrey, George Bush Sr and Al Gore.

Even a former Vice-President such as Walter Mondale in 1984 is hard to derail for the nomination. Dan Quayle admittedly toyed with a run nine years ago but dropped out when he realised that the whole nation was in danger of dying laughing. Every rule has to have its exception.

With neither George W. Bush nor Dick Cheney (tragically) available to vote for in 2008, the field in both the Republican and Democratic parties is open. This has drawn in a huge number of aspirants (many of whom have zero name recognition) who have started their bids earlier than is customary. The big players had to respond in kind, making it a marathon.

This in turn largely explains the cost of the election. In the past three months alone the hopefuls have raised collectively an astonishing $130 million (£65 million). Most of this is immediately ploughed back into advertising and organisation, even if it isn’t worth the candle at this stage of proceedings. In a slightly surreal circle of events candidates raise money to spend on boosting their status in almost meaningless opinion surveys in order to be able to snare more cash on the basis that, say, 14 per cent rather than 11 per cent of those who claim that they will vote in the South Carolina primary next February are keen on their candidacy.

The length and the cost I can tolerate (especially as I do not have to live in the US). It is the mad quality of this contest that bothers me. For if the pundits are correct, and there is evidence that they are, this is an election that no one can win.

How so? Let’s start with the Republicans. They have (until recently) had two front-runners, John McCain and Rudy Giuliani, whom the polls have consistently suggested are popular with plenty of people, though not core Republicans. They are electable but not nominatable. Mr McCain's difficulties are the three I’s: Iraq (he not only supports the war but would wage it more forcefully), immigration (he is boldly in favour of it, many in his party are more cautious) and incontinence (well, maybe not literally, but there is the outrageous assumption that a man of 72 is too old for the Oval Office). His effort has stalled so badly that last week his campaign manager and chief strategist departed with a degree of acrimony not seen since two of the key aides to Bob Dole in his doomed 1988 quest to be President were thrown off the campaign plane at Orlando airport, their baggage chucked after them, and told to find their own way back to Washington at their own expense. Mr Giuliani, on the other hand, has trouble with three G’s: gays (he likes them), guns (he doesn't like them) and God (three marriages, so far).

If received wisdom is correct, therefore, one of two other Republicans, Mitt Romney, the former Governor of Massachusetts, or Fred Thompson, a former senator from Tennessee, are more suitable for nomination. Unfortunately they aren’t very electable. Mr Romney because of his draconian conservatism and religion (many Americans think the Mormons are a cult). Mr Thompson because he is more famous for being an actor than a politician and even his most vigorous admirers would be pressed to identify a decent reason to make him President.

The Democrats have the flip side of the same scenario. Hillary Clinton and Barak Obama are certainly nominatable. Yet are they electable? Mrs Clinton’s national approval rate rarely exceeds 50 per cent and most voters believe Mr Obama to be a charming chap but too inexperienced and (for some) too black to assume the mantle of Washington and Lincoln. The next tier of contenders, John Edwards, ex-senator from North Carolina, and Bill Richardson, the Governor of New Mexico, seem much better suited to the task of taking the 270 votes necessary to triumph in the electoral college. Few analysts, nonetheless, can dream up a means by which either of these two can depose Mrs Clinton and Mr Obama.

Hence we are left, logically, with the conundrum that everyone who is electable cannot be nominated, while all those who might well be nominated are unelectable. This is plainly impossible, although it might explain the interest that is being expressed in Michael Bloomberg, the billionaire Mayor of New York, entering the frame as an independent. In any conventional year I would rate his chances of a half decent showing as negligible. If the mainstream nominees were Mr Obama and Mr Romney, that assessment would change.

Someone, after all, has to stand up on January 20, 2009 and take the oath of office. Who? It could be Snoopy at this rate.

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