The tears over coffee that turned round poll

It was the defining moment of the New Hampshire race: Hillary Clinton, the icy control queen of the Democratic party welling up with emotion - and it may have won her an improbable victory over Barack Obama.

The emotional moment in a cafe on the eve of Tuesday's poll was widely credited yesterday for bringing female voters back to the Clinton fold after their defection in the Iowa caucuses last week. Their strong support, as well as a surge for Clinton from traditional Democratic voters in the large towns of New Hampshire, propelled her to victory when polls were forecasting a double-digit win for Obama.

Clinton took 46% of the women's vote against 34% for Obama, exit polls showed; and women turned out to vote in greater numbers than men, making up 57% of the electorate. That participation, and the demonstration of sympathy for Clinton, succeeded in halting Obama's campaign in its tracks.

But while Clinton was unashamed about showing emotion in her victory speech on the night, she seemed anxious yesterday to shut down conversation about her momentary loss of control. In a series of television interviews on the morning shows, she attributed her astonishing win to a strong debate performance, and her efforts in the final hours of the campaign to meet as many voters as possible face-to-face. "I campaigned really, really hard across New Hampshire," she told CNN. "I had a lot of personal experiences with voters."

But none was as personal as her encounter with Marianne Pernold Young, with her disarming question of how Clinton managed to keep going on the campaign trail. The Clinton campaign had set up the coffee meeting with about a dozen undecided female voters in the seaside town of Portsmouth.

Clinton did not actually shed tears. But her voice quavered and her eyes welled up, and for a media that is driven to frustration by this most controlled of candidates that was a big story.

A local television reporter at the cafe went live as soon as Clinton's eyes reddened to report that she was crying. The clip of Clinton was rerun and analysed on television, and in the closing hours of the campaign Clinton gave even more interviews on her emotional state.

What saved her display from mawkishness and accusations from her enemies that she was indulging in self-pity was her swift and skilful pivot from the personal to the political.

"I couldn't do it if I didn't just passionately believe it was the right thing to do," Clinton began telling Young, her voice cracking. "I have so many opportunities from this country and I just don't want to see us fall backwards as a nation. This is very personal for me." She went on: "It's about our country, it's about our kids' futures, it's really about all of us together."

That display of emotion for her country - not merely her own presidential ambitions - probably helped Clinton capture the other key demographic elements of her victory, Democratic strategists said. Exit polls showed she performed even more strongly among low-income voters than she did among women, polling 47% against 32% for Obama. Clinton also performed well among those who see economy as the main issue of these elections.

Those strengths cushioned her against Obama's dominance over voters below the age of 24, where he polled 60% against Clinton's 22%, and his popularity among those who want a president to unite the country. Obama was seen by 51% of those polled as most likely to unite the country; Clinton by only 28%.

But the big mystery is how the opinion polls right up to election day got the result so wrong. Even the Clinton campaign confessed after the result was announced that its own private polling showed Obama winning by 11 percentage points, while Obama's campaign had internal polls that showed a 14-point margin between the pair.

Only 17% of voters made up their mind on the day of the election, and they split fairly equally between the two candidates.

That raised fears that Obama had suffered from concealed racism through what pollsters call the Bradley effect, a reference to the black mayor of Los Angeles, Tom Bradley, who lost an election for governor of California in 1982 despite having commanding opinion poll leads with white voters beforehand.

According to this theory, when faced with a black candidate, voters tell pollsters one thing and then do another in the privacy of the voting booth. In Iowa, where the caucuses mean voting is done in open sight, the Bradley effect could not take place.

What did certainly help Clinton, it appears, is a mini collapse in support for John Edwards, who was expected to poll around 20% or above but ended up with just 17%. Based on Edwards' support in Iowa, his older, more conservative voters were more likely to shift to Clinton than to Obama.

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