New Year’s Eve in Ames, Iowa, was achingly cold. The food was tepid and Barack Obama was late for his party. A thousand or so volunteers gathered in that university hall with balloons and “Stand for Change” signs. He arrived, buoyed by a poll showing him easing ahead: “We might just pull this thing off, Iowa.”

And so it was three days later that Mr Obama swept to victory in the Iowa caucuses with 38 per cent, his first important victory. His main rival, Hillary Clinton, was one of the best-recognised politicians in America who had spent the past seven years plotting a course back to the White House.

Mr Obama was very much the underdog. Little more than three years had passed since this virtual unknown, not yet elected to the US Senate, had burst on to the national stage with a speech at the 2004 Democratic convention. It had been quite a speech. “There is not a black America and white America and Latino America and Asian America,” he said, “there’s the United States of America!”

He was to return to this theme, time and time again he would speak of his “unlikely candidacy”. But he also sensed that voters were ready, after the Bush and Clinton presidencies, to take a chance on change. That message would not, alone, have been enough to win Iowa, which has an African-American population of less than 3 per cent. But unlike Mrs Clinton and John Edwards (the former North Carolina senator making his second presidential bid), his consistent opposition to the Iraq war had attracted armies of idealistic young supporters.

The Republican coalition was already breaking up. Mike Huckabee, a preacher who believes in creationism, came from behind to win his party’s caucuses with the backing of the evangelical Right. Second was Mitt Romney, whose Mormonism and recent conversion to social conservatism made him a figure of suspicion for many. Fred Thompson, a right-wing former senator and actor came third, and John McCain, who was running for a second time, was fourth.

Mr Obama had staked his entire campaign on a breakthrough win in Iowa. At his victory party, his voice boomed around the hall. “They said.” He paused. “This day.” Another pause. “Would never come.” It was not clear who “they” were. It sounded like he was talking about the Clintons. Within five days, these words were to sound like hubris.

Fantastic February

Mrs Clinton seemed beaten. Her own historic effort to shatter a glass ceiling and become America’s first woman president had become brittle, top-heavy, almost corporate. Her strategy had been to appear inevitable and watch her rivals hurl themselves in vain against her. Mr Obama refused and instead left it to the other candidates to attack her while he floated above the fray.

On the eve of the New Hampshire primary, Mrs Clinton’s eyes welled with tears when asked about how she coped with the pressures. The campaign was, she said, “very personal to me”. Some saw it as self-pity, but women voters, who perhaps recognised a little of their own struggles in her, supported Mrs Clinton over Mr Obama by 47 points to 34.

Mrs Clinton also won a narrow victory in Nevada and headed to South Carolina, where the black vote had solidified around Mr Obama. Her husband, Bill, once known as America’s “first black president”, was determined to drag Mr Obama off his pedestal but his remarks poisoned the atmosphere and the state went to Mr Obama.

In the McCain camp, things were turning around. Against the odds, he won New Hampshire, South Carolina and Florida, the state on which the former New York mayor Rudy Giuliani had staked so much. He was now the Republican front-runner.

After Florida John Edwards, who was John Kerry’s running-mate in 2004, dropped out of the Democrat race. Mrs Clinton was burning through cash so fast that her campaign was almost broke and she was forced to loan herself several million dollars to keep going.

February was the month when, according to her own script, she should have clinched the nomination. Super Tuesday, the vast coast-to-coast contest on February 5 across 24 states, was surely the day she would finish Mr Obama off? She did not. She won the big battles but her campaign made no effort to match Mr Obama in the smaller states. Super Tuesday ended in a score draw, and Mr Obama emerged with money in the bank and a plan.

He won the next ten states and on the night of victory in the Wisconsin primary he told a huge crowd in Texas: “Houston, I think we achieved lift-off here.” Mrs Clinton fired her campaign manager, Patti Solis Doyle.

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