 No one knows if former US Vice President Al Gore will return to politics, but he's definitely headed for Hollywood's red carpet, thanks to his climate change documentary 'An Inconvenient Truth.' 'Truth,' a big-screen adaptation of Gore's slide-show lecture calling for urgent action to curb man-made greenhouse gas emissions linked to global warming, was nominated for an Oscar on Tuesday as a best documentary feature. The nomination technically goes to the film's director, Davis Guggenheim, and its producers, Lawrence Bender ('Pulp Fiction') and Laurie David, the environmentalist wife of 'Seinfeld' co-creator Larry David. But Gore is the star and narrator of the film, which also profiles his long efforts to raise environmental awareness. The book version of 'An Inconvenient Truth' was published last year as a follow-up to his 1992 bestseller 'Earth in the Balance.' "An Academy Award nomination means more people are going to see Al Gore's message, and more people are going to wake up and help solve this problem," Guggenheim told Reuters. "Even people who are doubters are seeing this movie. You can only deny the truth for so long." Gore, who according to Guggenheim plans to attend the Oscars ceremony on February 25, said in a statement: "This film proves that movies really can make a difference." 'Truth' has grossed $24 million in US ticket sales alone to become the nation's third-highest-grossing documentary -- excluding concert films and Imax movies -- behind 'Fahrenheit 9/11' and 'March of the Penguins.' The film has taken in nearly $18 million more overseas. The nomination came hours before Gore's onetime political rival, President Bush, long skeptical about human-induced climate change, was expected to address global warming in his annual State of the Union speech. Bush, who defeated Gore in the contested presidential election of 2000, said before the film opened in May that he doubted he would see Gore's film. Oscar recognition would raise Gore's profile as his fellow Democrats line up to run for their party's nomination for president, although the former vice president under Bill Clinton said as recently as last week that he has no plans to run again in 2008. Also nominated for best documentary were 'Deliver Us from Evil,' about sexual abuse by a Roman Catholic priest; 'Jesus Camp,' about a religious camp; and two films about the war in Iraq -- My Country, My Country' and 'Iraq in Fragments.'