Democrat finest under starter's orders in long race to replace Bush in White House

'He has to win here - and he will.' Andrew Buncombe joins front-runner Howard Dean in Marshalltown, Iowa

Howard Dean looked tired. He smiled at the small audience before him and raised a clenched fist into the air. But as hard as he tried, his speech failed to click and he stumbled through some of his lines. He even urged people to go and vote on Wednesday when, of course, he meant Monday.

This is no time for politicians to be flagging. The people of Iowa will tomorrow select the Democratic candidate they want to take on George Bush head-to head in what will be a bitter and savagely fought presidential election in November. While the Iowa caucuses are just part of the process - indeed, fewer than 100,000 people will probably vote - the event's influence outweighs its size many times over.

The registered Democratic voters (and independents) of this midwestern Plains state have the power to decide whether a candidate's campaign lives or dies. For Dick Gephardt, the former Democratic leader of the House, it is make or break. "He has to win here to have any chance, and he will win," his campaign manager, Jim Murphy, told The Independent on Sunday.

For Mr Dean, still the party's national front-runner, anything but a win could knock the wind from his campaign and make him very vulnerable in the forthcoming New Hampshire primary, to be held a week on Tuesday - when two other heavyweight contenders, General Wesley Clark and Connecticut Senator Joe Lieberman enter the fray. Should a relative outside chance such as John Edwards come first, the North Carolina Senator's campaign would receive a huge boost, and the contest would really open up.

With just a day to go before voting, the three candidates are essentially in a statistical four-way tie with Massachusetts Senator John Kerry. The most recent poll shows him on 24 points, having opened up a five-point lead over Mr Dean and Mr Gephardt on 19 and Mr Edwards on 17 per cent. Anything could happen.

The details of the horribly complicated Iowa caucuses, where participants literally vote with their feet by gathering in various groups at caucus meetings across the state, are enough to confuse and put off all but the most obsessive aficionado of American politics.

But the caucuses and the primary polls in the other states that follow are best viewed with the broadest possible perspective. From the point of view of the Democrats, this is the start of a process to decide who will challenge the most polarising American President of recent years, whose neo-conservative-influenced policies and unilateral approach have stepped beyond the mainstream of political consensus.

Most national polls show the country evenly split between Democrats and Republicans each on 47 per cent, with the remainder of the public undecided. But the numbers fail to show the intensity of feeling aroused by Mr Bush, who - depending on one's point of view - is either tough, principled and determined, or corrupt, arrogant and stupid. It really is the case that people either love him or loathe him.

This is why the Washington outsider, Mr Dean, has been able to attract such a following of volunteers, with an estimated 35,000 pouring into this rural state in recent days to help his fresh, energetic campaign. "I drove for eight hours to get here to help," Walter Nowinski, 19, a history student at Michigan State University, explained at the event at which the tired Mr Dean was speaking, at a community college in Marshalltown on Friday evening.

"He is the person who has stood up to Mr Bush about the war. He is the person who has stood up about the tax cuts. I was drawn to him during the summer when he was the only one that said Bush was wrong."

Yet against this backdrop lurks a Republican Party machine of such efficiency and focus that the people of the rural state of Iowa and the young volunteers, who have given up their time to energise this campaign in a way probably not seen since 1972, might find hard to imagine. Whoever is eventually chosen by the Democrats will be in for a vastly difficult battle if they are to overcome the well-funded and currently popular incumbent, whose personal approval ratings stand at a possibly unprecedented 60 per cent.

But the people from the small towns and communities of Iowa have become veterans of the political process, having held the first of the states' polls since 1972. By tradition they are fiercely independent, do not suffer fools gladly and are suspicious of slick presentations and empty promises.

Experience also suggests that, for all the polls, the outcome of the caucuses is terribly hard to predict. This year's contest looks as though it will go down to the wire, with many people as yet undecided as to whom they will support.

Joyce Renzi, 60, a Marshalltown teacher who was watching Mr Dean, was one such voter. She had basically settled on voting for either Mr Kerry or the former Vermont governor, and she had been keen to come and hear him speak in person. "A lot of the things he was saying I believe," she said. "I do like the way that he was against the war, because so many just gave Bush the authority to do what he wanted to do. This guy stood up against it."

For a weary Mr Dean - who knows there is another 11 months of this if he is to get to the White House - there could be no better boost.

The crucial dates

19 January: Iowa caucuses kick off the primary season.

27 January: New Hampshire primary. Wesley Clark and Joe Lieberman, who are staying away from Iowa, enter contest.

3 February: Arizona, Delaware, Missouri, Oklahoma, South Carolina and New Mexico primaries. By now the field should have narrowed. If John Edwards is still in the race, he will try to pick up South Carolina, and Dick Gephardt would be banking on Missouri. North Dakota caucus.

10 February: Tennessee and Virginia primaries.

17 February: Wisconsin primary.

2 March: Formerly known as "Super Tuesday", when the biggest states ­ California and New York, plus Connecticut, Georgia, Maryland, Massachusetts, Ohio, Rhode Island, Vermont, Washington and Minnesota ­ hold primaries. Usually make-or-break day for a candidate.

9 March: Florida, Louisiana, Mississippi and Texas primaries. By now the candidate should be known.

26-29 July: Democratic Convention in Boston.

30 August-2 September: Republican Convention in New York.

2 November: Election day