"An Inconvenient Truth" has transformed Gore's public image from cold to cool.

From The Washington Post:

Over the past six years, Gore has become a heroic figure for the party's liberal left, thanks in large part to his early and steady opposition to the war in Iraq. And it's not just liberals who have taken to Gore. "An Inconvenient Truth," the film detailing Gore's lonely quest to raise awareness of climate change, is one of the most successful documentaries of all time and, as important, has transformed Gore's public image from cold to cool.

That renewed popularity has stoked speculation that Gore just may have another national race up his sleeve. "He's the Rocky Balboa of 2008," said Chris Lehane, a former Gore adviser.