Sarah Palin stands on stage as a crowd of exuberant Republicans, some wearing “I love pitbulls with lipstick” T-shirts, roar “Sar-ah, Sar-ah, Sar-ah” at their newfound heroine — a woman they believe has just transformed their hopes of winning the White House.

Behind her, having woken to the news that he has taken a lead over Barack Obama for the first time in nine months, is a grinning 72-year-old man, clapping along to the rhythm of the chanting as his running-mate basks in the adulation. His name is John McCain, by the way, but it is Mrs Palin the crowd has come to see.

With a guttural, rodeo-like defiance in her voice, stressing the words “guts” and “honour” — the qualities she feels that Mr Obama is lacking – the Alaskan lambasts the Democrat for failing to support the Iraq “surge”, when Mr McCain risked his presidential ambitions by backing it.

“In Iraq change happened and that’s a great thing for America, Senator,” she sneered to her crowd in the Kansas City suburb of Lee’s Summit, and the cheering and whooping began again.

As the McCain-Palin bandwagon rolled into the big battleground state of Missouri yesterday, it was buoyed by the latest Gallup poll showing that the Republican senator received an 11-point bounce from his nominating convention. Analysts believe that much of this gain is due to the electrifying effect of the 44-year-old Alaskan Governor.

One of the most crucial questions for both campaigns is to what extent Mrs Palin can attract white suburban women, a key swing group. Last night the McCain camp reacted with cautious optimism after a new ABC/Washington Post poll revealed a major defection of females away from Mr Obama. White women now support the Republican ticket by 53 per cent to 41. Before the conventions, the Democrat led among the same group by 12 points.

Mrs Palin has yet to be fully tested in the crucible of presidential politics. She will conduct her first solo primetime interview on Thursday, which aides to Mr Obama will watch like birds of prey. She will be pressed on her lack of foreign policy experience – she got her first passport only last year — and her full-throated conservatism.

Her social beliefs, as well as her performances, have enthused evangelical Republicans, whose support will be critical to Mr McCain in states such as Missouri. She opposes abortion, even after rape and incest, believes creationism should be taught alongside evolution in schools, and is a long-time member of the Assemblies of God, the largest Pentecostal denomination.

With evangelicals now volunteering in droves for the McCain campaign his aides believe the choice of Mrs Palin has so motivated the base that Republican states being targeted by Mr Obama – such as Virginia, Indiana and Montana – might now be beyond the Democrat’s reach.

Yesterday she sought to transmit some of that warm Republican glow enveloping her to her less popular running mate, dwelling at length on the “determination, resolve and sheer guts of Senator John McCain”. In a clear reference to Mr Obama, she declared: “There’s a time to campaign, and a time to put country first!”

A little girl with “Sarah” scrawled across the back of her white T-shirt waved and screamed: “Saraaaah!”

Mrs Palin went on: “There is only one man in this election who has ever really fought for you — my friend, John McCain!”

The Arizona senator took to the microphone, while hundreds of cameras were trained on his running-mate, leaving observers with the impression that many in the crowd would be even happier with a Palin-McCain ticket.

Such has been the power of the “Palin effect” that there has been a rush on her trademark Kawasaki 704 rimless glasses and upswept hairstyle — a look she calls “schoolmarmish” but which some Republican men of a certain age describe as the attractive librarian look.

After the melodrama of her 17-year-old pregnant daughter, and a sense that she had been a rushed, high-risk and largely unvetted choice, Mrs Palin has not only survived – so far — the intensive examination of her public and private life in Alaska; but she has also taken the fight to Mr Obama with a series of pugnacious performances that have fired up the Republican grass roots for the first time in years.

“They’re chanting John McCain too,” said Mark Salter, the Arizona senator’s long-time chief aide, when asked on the campaign flight to Missouri whether the Republican pair had decided to extend their time together on the trail because she was drawing the crowds. Having planned to make separate appearances yesterday, they will now stay together for at least two days. Aides say it is simply because they are having “fun” together.

Republicans move into narrow lead in polls

A USA Today/Gallup poll yesterday put John McCain leading Barack Obama by four points, reversing a seven-point deficit the week before (Tom Baldwin writes).

The underlying poll average, according to the RealClearPolitics website, suggests that the two campaigns are running neck and neck, while surveys taken in swing states suggest the Democrats have a slight advantage.

Indeed, a CNN poll published yesterday shows both candidates tied at 48 per cent.

One of the more significant findings from Gallup indicates that Sarah Palin, whose emergence has led to a new line in toys, below, has galvanised her party. Before last week Republicans were, by a margin of 47-39 per cent, less enthusiastic than usual. Now they are more enthusiastic by 60-24 per cent, narrowing Mr Obama’s longstanding advantage of 67-19 per cent on this measure.

There is scant evidence that Mrs Palin is doing more than hardening up a previously soft conservative base. An ABC poll on Friday reported that 85 per cent of Republicans looked favourably on the Alaska Governor, a figure that fell to 53 per cent for Independents and only 24 per cent for Democrats.

More worrying for the Republicans is another figure in the Gallup poll yesterday: 63 per cent of voters believe that Mr McCain would pursue policies that are too similar to those of President Bush.

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