Al Gore, elevated to almost prophetic status for his campaign against global warming, on Sunday night unveiled a new $300m advertising blitz intended to force a debate on climate change during the presidential elections.

The Nobel laureate, who appeared with his wife, Tipper, on the CBS programme 60 Minutes to roll out the effort, is to donate a share of his personal fortune to the campaign.

The couple told 60 Minutes that they would donate his Nobel prize money as well as a matching sum in addition to their profits from the book and the movie of An Inconvenient Truth. The movie brought the issue of global warming home to millions of Americans, as well as winning Gore an Oscar.

In this latest campaign, Gore said he hopes to persuade Americans that protecting the planet transcends the usual political divisions.

"We all share the exact same interest in doing the right thing on this," he told CBS. "Are we destined to destroy this place that we call home, planet earth? I can't believe that that's our destiny. It is not our destiny. But we have to awaken to the moral duty that we have to do the right thing and get out of this silly political game-playing about it. This is about survival."

The first television advertisements, which are to begin airing on broadcast networks as well as cable starting on Wednesday, will pair up the most unlikely partners in the movement to address global warming.

A clip aired on CBS showed the Reverend Al Sharpton sharing a sofa with the conservative preacher Pat Robertson. The two men acknowledge they agree on almost nothing - barring the need to deal with global warming.

Other spots will feature the Democratic Speaker of the House of Representatives, Nancy Pelosi, alongside New Gingrich, the conservative Republican who once held the same post.

The support from such conservative figures as Gingrich and Robertson marks a victory for Gore in his efforts to make global warming a cause for all Americans: evangelical Christians and fiscal conservatives as well as those on the left.

The recognition for his work in the Nobel prize and the Oscar had helped overcoe scepticism about whether climate change is man-made.

By this point, Gore argued, the doubters - which include the vice-president, Dick Cheney - had been isolated as a fringe group.

"I think that those people are in such a tiny, tiny minority now with their point of view," he told CBS. "They're almost like the ones who still believe that the moon landing was staged in a movie lot in Arizona and those who believe the earth is flat. That demeans them a little bit, but it's not that far off."

The 60 Minutes segment marked a rare appearance from Gore in the presidential race. After the crushing experience of losing the White House to George Bush despite winning the popular vote in the 2000 elections, Gore has become a cult hero for his passionate advocacy on the environment.

A swathe of Democrats continue to hope that Gore will return to politics - despite his protestations - or that he will weigh in to bring an end to the bruising contest between Hillary Clinton and Barack Obama.

Gore, despite his eight years as Bill Clinton's vice-president, has so far remained neutral in the race.

He also made it clear he has no intention of intervening to bring the contest to a close. "I'm not applying for the job of broker," he told CBS.

The advertising campaign is being created by an advertising agency whose work is familiar to American television viewers. The same agency produced advertisements for Geico car insurance using talking lizards and spoof of Planet of the Apes.

Gore acknowledged that so far Clinton and Obama have devoted relatively little time to discussing their platforms on climate change. But, as he told CBS: "I'm not finished yet."