A hoarse but ebullient Barack Obama has stormed into New Hampshire after his clear victory over Hillary Clinton in the Iowa caucuses reshaped the Democratic presidential race.

Mr Obama, whose message of generational change handed him victory in Iowa on a tidal wave of young and independent voters, arrived in the Granite State yesterday and proclaimed to a cheering crowd in a vast aircraft hangar in Portsmouth: “Our time for change has come. And four days from now, New Hampshire, you have the chance to change America!”

Mr Obama’s eight-point victory over Mrs Clinton in Iowa appeared to be a stunning vindication of his passionate call for a new, less divisive era in US politics. But he now faces perhaps the greatest challenge of his campaign: a wounded Mrs Clinton in a state where she enjoys far deeper support than she ever did in Iowa.

The former First Lady, who finished third just behind John Edwards, will now use every element of the ruthless political machine behind her, and connections in New Hampshire built up over years with her husband, Bill, to halt Mr Obama’s momentum.

As soon she arrived in New Hampshire, Mrs Clinton immediately launched far sharper and more personal attacks on Mr Obama. In a reference to his self-admitted past drug use, she told a cheering crowd at Nashua airport: “Of all the people running for president, I’ve been the most vetted, the most investigated, and — my goodness — the most innocent, it turns out.”

In a later press conference, she said she would be “drawing contrasts between what I’ve done for 35 years and what my leading opponents have done.”

With Mr Obama seeking to become America’s first black president, his victory in an overwhelmingly white Iowa was all the more remarkable because he attracted record numbers and almost every demographic. He carried its five biggest counties, its conservative west, the rural stretches along the South Dakota border, university students, and even outpolled Mrs Clinton among women, her core constituency.

“They said this day would never come,” Mr Obama said. “My throat is still a bit torn up but my spirits are high. Because last night America began down the road to change.”

The first-term senator from Illinois, referring to Mrs Clinton’s attempts earlier in the campaign to run as the inevitable candidate, he said: “This is the moment when the improbable beat what Washington always said was inevitable.”

He chided his opponents for calling naive his campaign slogan “hope”. And in the soaring rhetoric that has marked his campaign he even declared that he carried the same kind of hope that had allowed America to gain its independence.

Another victory for Mr Obama in New Hampshire on Tuesday could give him unstoppable momentum as the closely bunched primary calendar unfolds in the next three weeks. But he and his aides are acutely aware that New Hampshire presents very different political terrain from Iowa, and is a state where Mrs Clinton has several advantages. She leads by seven points, according to the latest poll. Her support is solid: among Democrats who say they have made a definite choice, she is supported by 46 per cent, Mr Obama by only 28 per cent.

The state’s more obdurate electorate has more of an appetite for attack advertisements than the gentler Midwestern sentiments that mark Iowa. New Hampshire has often righted an Establishment candidate’s ship after it has been blown off course in Iowa.

Mr Clinton is still beloved by New Hampshire’s Democrats and the couple have spent years assiduously courting its voters. Their ground organisation is formidable here.

Yet Mr Obama heads to events across New Hampshire this weekend having beaten two tough opponents in Iowa — Mr Edwards had campaigned there for four years — and amid a creeping sense that this year America just might be ready to embrace a black, 46-year-old candidate called Barack Hussein Obama. He has run a civilised, almost cerebral, campaign, and is promising a decisive break with the bitterly contested politics of the baby-boom generation that have marked the presidencies of Mr Clinton and George W. Bush.

Mr Obama has another advantage: nearly 45 per cent of New Hampshire’s registered voters are independents, the key to John McCain’s victory in the 2000 Republican primary, but who appear this week far more ready to flock to the candidate of change.

Mr Obama has enormous obstacles to overcome, not least the still formidable candidacy of Mrs Clinton, but his rise to become Democratic frontrunner is nevertheless a remarkable feat. Over the summer Mr Obama appeared becalmed, and sometimes meandering. Many believed that he lacked the steel to take on Mrs Clinton’s apparently unstoppable juggernaut, let alone make it all the way to the White House. But in October, as Mrs Clinton began to stumble, Mr Obama also sharpened his message and began to rise in the polls. The Clinton campaign responded with a series of clumsy attacks that backfired, not least a memo to reporters revealing that Mr Obama had written a kindergarten essay saying that he wanted to be president. They contrasted those childish writings with his claims this year to have harboured only recent ambitions for the White House.

“This feels good,” Mr Obama said to the New Hampshire crowd. And then, with a dig at Mrs Clinton, added: “Just how I imagined it when I was talking to my kindergarten teacher.”

Democrats in Iowa

Winners and losers

GOING UP

Barack Obama Senator seeking to become first black president with a message of change and bringing America together again. After a stunning victory in Iowa, he now must repeat the trick in New Hampshire. Questions remain about whether he can build similar excitement nationally in big states where he cannot force himself on voters with the intensity he has shown in the early contests.

65.2% Chance of winning New Hampshire 43.8% Chance of winning Democrat nomination 27.5% Chance of winning presidency

GOING DOWN

Hillary Clinton Senator and former First Lady who has campaigned on her experience as an “agent of change”. Stripped of her aura of inevitability and invincibility, she must turn her campaign around fast and convince voters that a Clinton Restoration to the White House would deliver the change for which they yearn. But she maintains a strong lead in national polls and New Hampshire may be more fertile ground.

35.2% Chance of winning New Hampshire 53.7% Chance of winning Democrat nomination 32.2% Chance of winning presidency

GOING SIDEWAYS

John Edwards former Senator and vice-presidential nominee in 2004 who has reinvented himself as an angry populist. Did well to scrape second place in Iowa but, with Obama now clearly the alternative to Clinton, he is expected to struggle in New Hampshire where union votes matter less and he will be outspent once more.

1.6% Chance of winning New Hampshire 2.3% Chance of winning Democrat nomination 1.3% Chance of winning presidency

Source: politics futures trading at realclearpolitics.com

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