America is huge; its multi-ethnic population concentrated in large metropolitan areas. Yet a disproportionate say in deciding which Republican faces Bill Clinton in November will be wielded today by a state of barely 1 million people, which is 98 per cent white, very rich, mostly rural and suburban, highly conservative, and which boasts the highest per capita membership of the National Rifle Association in the United States, bar Alaska.
The reason is simple. In 1949, New Hampshire passed a law allowing voters in its primary - already the first on the election calendar but not yet of national significance - to choose not just delegates to the party- nominating conventions, but delegates committed to a particular presidential candidate.
As a result, since 1952 when Dwight Eisenhower won without setting foot in New Hampshire, the state has been where the battle starts for White House hopefuls - a maker and breaker of Presidents.
Though it contains just 0.4 per cent of the US population, New Hampshire counts for far more in the selection of a nominee than California, the most valuable state in the general election. But the California primary comes much later, when nine times out of ten the victor is already known, and as a rule it passes virtually unnoticed.
Pre-eminence of course breeds jealousy. This year, Delaware and Arizona sought to move their primaries ahead of New Hampshire. But ultimately they did not, partly because of New Hampshire's ability to press candidates to boycott them, and partly because of the media's abiding interest in New Hampshire, cold and all.
For all its shortcomings, the state does have advantages. The small, highly educated electorate offers a rare opportunity for "retail politics", a last chance for voters to meet candidates in person before the campaign turns into a hi-tech transcontinental whirlwind, this year of 30 primaries in six weeks.
In 1992, the legend was dented when Mr Clinton became the first President in 40 years not to have won New Hampshire. But its mystique endures, and these days it is an American institution as entrenched as Thanksgiving or the Superbowl.
Those who wish to sample it, the author Charles McDowell once wrote, should set out from Boston and "seek out the road that follows the Merrimack river due north into the snowy hills and unreality. That way lie the beauty and the gentle madness of New Hampshire in the winter of its presidential primary."
The madness may be less gentle these days. But every four years candidates, their staffs and reporters by the thousand do exactly as Mr McDowell instructed.Reuse content