Separating the two vice-presidential nominees yesterday were 4,000 miles and a fortnight of dramatically differing political fortunes.

Sarah Palin had travelled home to Alaska, the far-flung frozen corner of the United States that often does not even feature on maps of the country, where she continued to bask in the limelight and the attention of a nation.

Few will have noticed that Joe Biden was back trudging along the campaign trail in the battleground state of Ohio. The previous night, he had acknowledged that Hillary Clinton “might have been a better pick than me” as vice-presidential running-mate. Many Democrats were left quietly nodding in agreement.

At the end of the Democratic convention in Denver two weeks ago, it had all seemed so different. The conventional wisdom was that Barack Obama had made a clever, if cautious, choice in Mr Biden – a Senate veteran with the foreign policy expertise and appeal to white working-class men that he lacks.

John McCain’s decision to pluck Mrs Palin from relative obscurity was seen as a desperate gamble that risked undermining a Republican campaign built on his experience and claim to have better judgment. But she has become an almost elemental force in this election, reversing the Democrats’ long-standing lead among white women, galvanising her party’s conservative base and energising Mr McCain himself.

When Mrs Palin flew back to Alaska on Wednesday night, television channels were treating her arrival much as they would that of the Pope, breathlessly reporting scenes from the empty tarmac as they waited for her aircraft to touch down.

She had spent days huddled with Republican advisers preparing for her first major interview. This took place in her home state last night and she used it to insist that if “privileged to be elected to serve this country – I’m ready”.

She was questioned vigorously on foreign policy, telling ABC News that countries such as Ukraine and Georgia should be admitted to Nato. Asked if that meant America should go to war with Russia if Georgia was attacked again, she replied: “Perhaps so. I mean, that is the agreement when you are a Nato ally.”

Mrs Palin appeared flummoxed when asked if she agreed with the “Bush doctrine”, answering in rambling fashion about the President’s world view and explaining that terrorists had attacked the US seven years earlier “because they do not believe in American ideals”. When it was explained that the doctrine was for preemptive strikes against any threat, she replied: “We’ve got to have all options out there on the table.”

Later, the TV cameras were back in tow as she attended a farewell party for her eldest son, Track, a soldier being posted to Iraq on a day when much of America was commemorating the anniversary of 9/11. Mr Obama and Mr McCain stood together at Ground Zero in New York.

Mr Biden appeared at the American Legion Post 703 in Parma, Ohio. On Tuesday he had been accused by the McCain campaign of having “sunk to a new low” after referring to Mrs Palin’s fifth child, born in April with Down’s syndrome.

Rick Warren, the Christian Evangelist leader who hosted the two presidential candidates for a televised forum last month, said that Mrs Palin had called him asking for advice and Bible verses on how to deal “with the unfair, unjust attacks and the mean-spirited criticism that comes in”.

In her interview last night Mrs Palin tried to explain her remark this summer that American soldiers were “on a task that is from God”. She said: “I would never presume to know God’s will or to speak God’s words [but] let us pray that we are on God’s side . . . there is a plan for this world and that plan for this world is for good.”

Some Democratic strategists believe that her power is a fad that will fade in the face of scrutiny of her exaggerated claims to have opposed spending projects such as the notorious “Bridge to Nowhere” in Alaska. Bob Shrum, who advised John Kerry four years ago, dismisses her as “Miss September”. Others suspect that the polls are pointing to a trend. Doug Schoen, who worked on Bill Clinton’s campaign in 1996, said there was “deep-seated unease that the message has gotten away”.

Mr Obama himself appeared on the David Letterman show on Wednesday night to acknowledge “she has been a phenomenon” and to mock his own suddenly falling star. “I mean, as somebody who used to be on the cover of Time and Newsweek, those were the days. I had a recent offer with Popular Mechanics, centrefold with a wrench.”

He also tried to make light of his remarks comparing Republicans offering change to putting lipstick on a pig. Keep in mind that, technically had I meant it this way – she would be the lipstick. The failed policies of John McCain would be the pig . . . I mean, just following the logic of this illogical situation.”

He also had to defend his decision to pick Mr Biden, saying: “You know, the way I thought about it was, ‘Who’s going to help me govern? Who’s the person I want in the room if we’ve got a big decision to make?’.”

Palin the target

“[Sarah Palin is a candidate] whose primary qualification seems to be that she hasn't had an abortion”

South Carolina Democratic Party chairwoman Carol Fowler

“Barack Obama was a community organiser like Jesus. Pontius Pilate was a governor [like Sarah Palin]”

Obama-supporting Congressman Steve Cohen of Tennessee

“It’s like a really bad Disney movie. You know, the hockey mom [saying], ‘Oh, I’m just a hockey mom from Alaska!’ And it’s like, she’s facing down Vladimir Putin using the folksy stuff she learnt at the hockey rink. It’s just absurd”

Actor Matt Damon

A list of books, including Tarzan of the Apes and Huckleberry Finn, is circulating the internet with claims that Sarah Palin wanted them banned from the public library when she took over as Mayor of Wasilla, Alaska, in 1996. The list includes four volumes of the Harry Potter series, the first of which was not published until 1997

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