Every four years Iowa and New Hampshire are transformed from a pair of obscure American states into the throbbing, if frozen, hub of the political universe.

Next month their citizens will once again make the first pick from 16 candidates seeking the Republican and Democratic nominations for the White House.

Strange and unhealthy rituals accompany this quadrennial phenomenon. The next president of the United States is expected to cross thousands of barely undulating Iowan fields, chew corn dogs (a deep-fried sausage covered in batter and white bread), attend pig roasts, pay homage to the state fair's 600lb butter cow and, as likely as not, lick a “Blue Bunny” from the self-proclaimed ice-cream capital of the world at the Wells Dairy, Le Mars.

For months candidates have been driving up and down dozens of thickly wooded mountainsides in New Hampshire, then sweating through conversations in overheated front rooms, pressing the flesh in overcaffeinated diners and shivering in refrigerated town halls.

Just why those seeking to become “Leader of the Free World” must prostrate themselves in such a fashion before these two states — with a combined electorate that accounts for less than 1.5 per cent of the US population — is a source of bafflement and resentment for the rest of America.

Other, more representative states, containing a metropolis or significant numbers of ethnic minority voters, have tried valiantly to gatecrash. However, Iowa and New Hampshire, stubborn sentinels of a status that has grown over the past five decades, have responded by moving their dates farther forward.

Despite talk about leading candidates such as Hillary Clinton and Rudy Giuliani pursuing a “big-state strategy” or even bypassing Iowa, they have fallen into line with other would-be presidents by lavishing more time and money on the “first-in-the-nation” contests than ever before.

This year Iowa has held no fewer than 1,798 presidential campaign events and New Hampshire has hosted 940. By comparison, neighbouring states such as South Dakota, Nebraska, Maine and Vermont have amassed a total of 14.

The verdict of the Iowa caucuses on January 3 and the New Hampshire primary elections five days later could propel one candidate towards the White House or will, at the very least, pare them down to a shortlist of perhaps half a dozen.

It is possible for the likes of Mrs Clinton, for the Democrats, or Mr Giuliani, for the Republicans, to lose both states and still go on to take their party's nomination. Bill Clinton skipped Iowa altogether in 1992 but did well enough by coming second in New Hampshire to be seen as the “comeback kid”, developing the momentum to catapult him into the Oval Office.

These two states have more often been places where front-runners have crashed and dark horse candidates, such as Jimmy Carter in 1976, have come charging out to win.

In the past month the most compelling story has been the emergence of the Republican Mike Huckabee from single figures in the polls a few weeks ago to take the lead among his party's caucus-goers in Iowa.

His campaign manager, Eric Woolson, describes his “sheer excitement” at being part of a phenomenon that has cost a few hundred thousand dollars compared with the millions spent by rivals on TV advertisements.

“It's been a genuine grassroots exercise, neighbours talking to each other, church members chatting to friends,” he said. “There is something about Iowa which means they take a real measure of the candidate out here.”

In 2004 Howard Dean seemed a certainty for the Democratic nomination before coming third in the Iowa caucus behind John Kerry and John Edwards. Even as he emitted his infamous “Dean scream” at a rally for supporters that night, he was already heading for another defeat in New Hampshire.

Mary Beth Cahill, Mr Kerry's campaign manager, believes that his success was achieved through individual conversations with voters in which candidates are expected to set out their positions on everything from ethanol subsidies to the North Korean nuclear programme.

“The biggest asset you have is the candidate's time,” she says. “We cobbled together a list of supporters for him to meet and, out of all the time we had, that was the best spent. Without Iowa and New Hampshire, Dean would have been the Democratic candidate.”

That direct contact is the justification for their continued role in exercising such profound influence over the presidential nomination process.

Dayton Duncan, who grew up in Iowa and now lives in New Hampshire, where he has worked on many Democratic campaigns, believes that these elections provide “unscripted moments with real voters” that test candidates in a way that does not happen when the wagon moves on to bigger states.

“They are running to be president of the most powerful nation on Earth but it feels like they are running for sheriff — that is what makes it interesting and worthwhile,” he says. And, while there is no reason why the nominating process could not begin in other small states, “we have been doing it for a long time and we have a certain tradition”.

Mr Duncan says that critics should listen to the questions asked of candidates. “They are about national, international, issues. People take themselves seriously — some expect to meet presidential candidates in person — they feel their vote is important.”

New Hampshire, the “live free or die” state, has become slightly more suburban in recent years but remains individualistic, staging a primary election in which voters cast their ballots in secret.

Unlike Iowa, where born-again Christians account for almost half the Republican caucus-goers, New Hampshire has one of the lowest rates of church attendance of any state. Mr Huckabee, a Baptist minister, is still struggling for support there while the likes of Mr Giuliani and John McCain — who are regarded with varying levels of suspicion by “values voters” — expect to do badly in Iowa but hope to recover in New Hampshire.

The communitarian nature of Iowa is reflected in its caucus system, in which those who turn up to one of the 1,784 precincts on a typically freezing January night express their will publicly, clustering in knots of supporters for each candidate. These neighbourly Midwestern voters are said to dislike shrill negative campaigns.

The unpredictability of the Democratic contest in Iowa is amplified by a rule allowing those backing failing candidates — who do not meet the “viability” test of having 15 per cent support in the caucus room — to redistribute their support. Chaos often ensues, with other groups cajoling, persuading and pleading with these floating voters to join them.

Turnout in the caucuses is notoriously low, with only 124,000 voting in the Democratic contest four years ago. Mrs Clinton and her chief rival, Barack Obama, hope to swell these numbers next month, with about half their pledged supporters said to have never attended a caucus before.

Both are acutely aware that Mr Dean was relying on similar support in 2004. They are distributing videos designed to raise the “comfort level” of these new voters and staging dress rehearsals to stop them from being intimidated by this arcane and peculiar process.

Mr Edwards, who has been campaigning in Iowa almost non-stop since 2003, chooses to flatter Iowa and New Hampshire, describing them as the “guardians” of the American presidency. Joe Biden, a Democrat candidate running a distant fifth in the polls, can afford to be honest, saying that voters in these two states have once again “been seized by their own importance”.

THE BIG TWO

New Hampshire

Population 1.3m

Ethnic breakdown: White 95.1% Black 0.7% Asian 1.3%

Percentage of state working in agriculture 0.9

Iowa

Population 3m

Ethnic breakdown: White 92.6% Black 2.1% Asian 1.2%

Percentage of state working in agriculture 4.4

US average

State population 5.8m

Ethnic breakdown: White 81.7% Black 12.9% Asian 4.2%

Percentage in agriculture 0.7

Sources: Almanac of American Politics; CIA World Factbook

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