Al Gore was once hailed by Democrats as the man who could save America from George W. Bush. Six years after his failed presidential bid, he is back on the public stage trying to save the world instead.
Having faded from prominence since the Florida voting fiasco that relegated him to runner-up in the 2000 White House race, the former politician known for his robotic style and dull persona has staged a red-carpet comeback to rave reviews.
The enthusiasm with which his new documentary film on climate change has been received, coupled with the passion and charisma he is said to exude in its lead role, has got Washington buzzing with speculation. Could the reinvented Mr Gore be persuaded back into politics? Might he even take a tilt at the presidency? Could he be the Un-Hillary some of them seek?
'If he's the guy we see today, I think he'd be formidable,' gushed Democratic consultant Joe Trippi, who added that Mr Gore 'could wreak havoc' on the 2008 presidential race should he run as an independent.
If Mr Gore is tempted, he isn't letting on just yet, making it clear that he would rather keep the buzz focused on the film's critical environmental theme.
'I don't intend to be a candidate ever again,' he told NBC's Today show on Wednesday, appearing to put a lid on the idea of a return to politics, until he added: 'I'm not at the stage of my life where I'm going to say 'Never in the rest of my life will I ever think about such a thing'.'
In separate comments to staff at an Atlanta-based political news service, he kept up the suspense. 'I'm a recovering politician ... but you always have to worry about a relapse,' he said.
The 58-year-old, who served two terms as vice-president to Bill Clinton, was feted by appreciative crowds and juggled demands for more than 20 interviews a day when he appeared at the Cannes Film Festival this week for the European premiere of An Inconvenient Truth.
'Even with Tom Hanks, Bruce Willis, Penelope Cruz, Jamie Foxx and Halle Berry here for the film festival, the hottest star in town is Al Gore,' reported Arianna Huffington, a political columnist. 'Gore 2 is a revelation, and a critical smash.'
The movie had already been hailed in the US - where it made its debut at the Sundance Film Festival in January to a standing ovation and opened nationwide this week - as 'mesmerising'. The Washington Post called him a 'hero'. Time magazine dubbed him 'a rock star'. Asked at a press conference how he should be addressed, he deadpanned: 'Your Adequacy.'
The 96-minute film chronicles his mission to convince people of the dangerous realities of global warming and warns that mankind has just 10 years to reverse the global warming trend before the planet crosses a point of no return.
It is a subject so close to Mr Gore's heart that he was once derided by President Bush's father, George H. Bush, as Ozone Man - a label that has stuck through his post-White House years, which he has spent travelling the world to deliver 1,000 lectures on the subject.
Those who know him say that the upset of losing the most controversial presidential election in US history six years ago affected him deeply. He has worked up a sense of humour about it, though. 'I am Al Gore. I used to be the next president of the United States of America,' he tells his audiences, feigning annoyance when they titter.
To Albert Arnold Gore Jnr, the presidency was a crown he had coveted since he entered politics in 1976. The son of a US senator, his childhood was divided between Washington DC, where he lived in a hotel room while attending school, and summer holidays on the family farm in Carthage, Tennessee.
Despite being opposed to the Vietnam war, he enlisted in the army in August 1969 and trained as a military journalist. After marrying school sweetheart Mary Elizabeth Aicheson, known as 'Tipper', he headed to Vietnam as a field reporter with the 20th Engineer Brigade, stationed at Bien Hoa Air Base near Saigon. He received an honourable discharge in 1971.
His experience in Vietnam 'didn't change my conclusions about the war becoming a terrible mistake', he would later say. Years later, he would become one of the most vocal, early critics of Mr Bush's war in Iraq.
Back in Tennessee, he worked for five years as a newspaper reporter and went to law school before a successful run for the US House of Representatives in 1976.
He was re-elected three times and then, in 1982, to the US Senate. Known for his high-profile image, he was nicknamed 'Prime Time Al'.
He ran for the presidential ticket in 1988, but was beaten to the Democratic candidacy by Michael Dukakis. When his six-year-old son Albert was seriously injured in a car accident in 1989, he abandoned plans to launch a campaign for the next presidency so he could help the boy through his recovery.
When Bill Clinton won the Democratic nomination in 1992, he invited him to become his running mate and Mr Gore was inaugurated as the 45th vice-president of the United States in January 1993.
During their two terms in office, they presided over one of the longest periods of economic growth in US history, the creation of 22 million jobs, the highest ever rates of home ownership, the lowest unemployment rate in 30 years, the lowest poverty rate in 20 years and the conversion of a large budget deficit into the largest ever surplus.
Mr Gore was particularly noted for his shake-up of federal government fraud, waste and bureaucracy, for pushing environmental issues and a pro-abortion stance, and for his foreign policy know-how.
Yet when it came to the 2000 election, he never quite managed to gain the edge he needed in certain crucial states for a victory over the Republican Bush - a fault that his running mate, Senator Joe Lieberman, would later blame on Mr Gore's misplaced 'populist' message.
Despite Democratic hopes - and a pre-election episode of The Simpsons, in which Mr Gore was shown confidently measuring the curtains in the Oval Office - it all came down to Florida, where botched ballot papers forced several weeks of judicial wrangling. The Supreme Court ruled Mr Bush the winner by just 537 votes.
But it is his work as an eco-crusader that matters to him most.
'We face a deepening global climate crisis that requires us to act boldly, quickly, and wisely. Our ability to live on planet Earth is at stake,' he says. 'I even believe that there is a chance that within the next two years, even Bush and [Vice-President Dick] Cheney will be forced to change their position on this crisis.'
Mr Bush may be a tough nut to crack though. Asked if he planned to see the Gore film, he gave a two word answer. 'Doubt it.'