Al Gore will be treading the red carpets of Hollywood on Sunday when he attends the Oscars where his climate change film, An Inconvenient Truth, has been nominated for the best documentary award.

But the man whom many Democrats still insist beat George Bush in 2000, is also keeping a toe-hold on the 2008 presidential contest by refusing to rule out, categorically, making another bid for the White House.

When asked — as he is frequently — whether he will stand again, Mr Gore professes exasperation before saying: “I can’t foresee circumstances in which I would.”

This is a similar form of words to those repeatedly used by Michael Heseltine to defuse speculation that he was planning to challenge Margaret Thatcher for the leadership of the Conservative Party — until he did just that.

Mike Feldman, a long-time friend and adviser to Mr Gore, told The Times: “Anybody who knows Al Gore will tell you that he is already involved in a campaign against global warming — and that is the only campaign he is involved in. But it’s right to say he has not closed the door (on the presidency) entirely. He is 58 years old and is not willing to do that just yet.”

Donna Brazile, who ran his last presidential campaign in 2000, last month teasingly told activists that she had not decided who to back for 2008. “Wait till Oscar night,” she said. “I’m dating, I haven’t fallen in love yet.”

Mr Gore has reinvented himself: a wooden performer seven years ago, he is now a passionate and visionary advocate for action against climate change.

And unlike Hillary Clinton, with whom he had a testy relationship in her husband’s White House, he opposed the Iraq War from the outset.

Mrs Clinton, along with other Democratic candidates, is now said to be anxiously studying his girth, which expanded rapidly when he left office six years ago, as a measure of his political ambitions. If they can get their arms around him, he might be standing or, as Ms Brazile put it: “on Oscar night, if Al Gore has slimmed down 25 or 30 pounds, Lord knows.” She believes that over a drawn-out race for the presidency, other candidates will be facing “burn-out” by the autumn. “Al Gore could enter the race tomorrow, September or November.

“A lot of candidates got in early for name recognition, or because they need the time to raise money, [but] Al Gore is a much different man than he was in 2000. He has the credibility and the stature. He has become a cultural hero,” she said.

Over the coming months he can easily maintain a higher public profile than many other candidates. In addition to the Oscars this weekend, Mr Gore has also been nominated for the 2007 Nobel Peace Prize in October.

Nor should fund-raising be a problem for a man who is said to have amassed a personal fortune worth as much as $100 million (£50 million) by acting as an adviser to Google and Apple Computer since leaving the White House.

All of this does not, of course, mean Mr Gore will stand. But this weekend he stands astride the two great gossip factories of America: Washington on the east coast and Hollywood on the west. And, for the moment he seems happy, to keep the ru-mours alive.

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