American Idol gives back and the U.S. presidential candidates want to help.

All three major party candidates -- Republican John McCain and Democrats Hillary Clinton and Barack Obama -- are participating in Wednesday night's Idol Gives Back episode, the second charity drive that takes advantage of the talent show's wide audience and numerous phone lines.

Idol Gives Back is boasting a huge celebrity guest list for its charity show this year. Aside from A-list stars, British Prime Minister Gordon Brown is joining the U.S. politicians. Last year's effort raised $76 million and included former Presidents George H.W. Bush and Bill Clinton and Great Britain's Prince Charles.

Obama's brief remarks include a commendation for the effort, which will raise funds for  The Children's Defense Fund, Children's Health Fund, The Global Fund, Make It Right, Malaria No More and Save the Children.

"I’d like to say a few words not just as the father of two young girls who are big American Idol fans, but as someone who cares deeply about what tonight’s show is all about," he says in his taped appearance. "Whether it’s across the street or around the world, Idol Gives Back is proving that when ordinary people come together, they can do extraordinary things. So I want to commend American Idol for the example they’re setting and the work they’re doing. And I hope that everyone who’s watching will make a contribution to Idol Gives Back, and help make this world a more just, more equal and more hopeful place to live."

Idol Gives Back appears on FOX Television and is sponsored in part by News Corp., the parent company of FOX News Channel and FOXNews.com.