Throughout their long primary campaign this year, Democrats made much of the fact that their progressive party was presenting a historic choice to the nation; the first black man or woman in the Oval Office. With the selection yesterday of Sarah Palin as his vice-presidential running-mate, John McCain dramatically stole his opponents’ clothes.

But at first sight, the choice certainly looks like a risky stunt.

Cleverly and improbably, the McCain campaign succeeded in keeping secret the identity of his choice until almost the last minute before the official announcement of the candidate.

That alone was certain to sharpen the pivot of public attention away from Barack Obama’s acceptance speech on Thursday night at the Democratic Convention in Denver.

But if the process helped along the change of political subject in America from non-stop Obama, the choice itself was a true conversation-stopper.

First, Mrs Palin was not believed to be on the final shortlist of candidates. Second, while the Democrats failed to choose a far more prominent woman for their presidential or vice-presidential candidate, to the anger of some women voters, the Republicans — that supposedly reactionary bunch of woman-hating Neanderthals — are putting a woman within a heartbeat of the presidency.

The aim is presumably at least in part to win over some of those disillusioned female Democratic voters. Even if they disagree with her views, many American women will surely be thrilled at the sight of a working mother elevated to potentially the second-highest office in the land.

In her first appearance beside her running-mate yesterday she immediately drove home the point, paying tribute to Hillary Clinton and Geraldine Ferraro, who ran as the Democratic vice-presidential candidate, saying: “The women of America are not finished yet. We can shatter that glass ceiling.”

The selection will also energise what was shaping up to be a somewhat nervous and under-motivated Republican Party as it gathers for next week’s convention in St Paul, Minnesota.

Mrs Palin is a strong conservative. She is fervently anti-abortion and this year gave birth to her fifth child, who has Down’s syndrome. After the birth she and her husband said: “We knew through early testing he would face special challenges, and we feel privileged that God would entrust us with this gift and allow us unspeakable joy as he entered our lives.” She hunts, shoots and fishes, and bolsters Mr McCain’s standing with conservative voters, many of whom did not vote for him in the primary election and remain sceptical about his credentials.

But she represents a huge gamble. She lacks the experience that some consider necessary to be vice-president, ready to step into the Oval Office should anything befall the 72-year-old Mr McCain. Is she — at 44, a governor for less than two years and until 2006 the part-time mayor of a small Alaska town — equipped to sit opposite Vladimir Putin or Hu Jintao? Or, for that matter, the Democratic leadership in Congress?

Mr McCain has made much of Barack Obama’s lack of experience, but may now have undercut that argument. Democrats will surely relish the prospect of the vice-presidential debate between Joe Biden and Mrs Palin. The worry that some Republicans were voicing quietly yesterday is that what seems a clever and exciting choice today might look like a disastrous display of poor judgment in a couple of months. But Mrs Palin brings advantages to the campaign as it seeks to defy the odds and win a third straight presidential victory for the Republicans. She has no connection to the Bush Administration, which will help to deflect the Obama campaign’s charge that Mr McCain is running for President Bush’s third term. As Governor of Alaska she is about as far removed from Washington as it is possible to be. The McCain campaign intends to contrast that with the inside-Washington double ticket of Obama and Biden.

Perhaps most impressively, in just a year and a half in office in Alaska she has established a reputation as a tough reformer. She is also a staunch advocate of expanding domestic drilling for oil, popular among oil-rich Alaska and among Americans as a whole. At her first appearance on the stump yesterday alongside her running-mate, she seemed assured and steady. But her selection adds a startling new uncertainty into the presidential race, a risky gamble for the Republicans but a complicating headache for the Democrats.

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