Some activists at the Public Broadcasting Service seem jealous that CNN is alone in offering yet more free debate time to the Democrats. Last year, PBS offered a liberal debate forum to both parties, hosted by black activist Tavis Smiley. Cornelia Dean reports on The Caucus blog at The New York Times that some PBS producers want a science debate between the Democrats with a group called Science Debate 2008: 

Senators Hillary Rodham Clinton and Barack Obama have turned down a chance to debate science issues next week in Philadelphia, but the would-be organizers, a group of scientists and others called ScienceDebate2008, hope to arrange an alternative in Oregon, which holds primaries May 20.

Ty West, senior producer for the PBS weekly news program NOW, said he has been working with the group in hopes of scheduling a debate either May 2 or May 9 to be broadcast by the Public Broadcasting System from Portland State University. He said the effort was a cooperative effort involving WNET in New York, which produces NOW, WGBH in Boston, which produces the science program NOVA, and WOPB, the public broadcasting station in Portland.

The debate effort has been endorsed by leading scientific organizations, eminent researchers including Nobel laureates, university presidents, politicians of both parties and others. Its goals are explained on its Web site, ScienceDebate2008.com.

The official invitation promises PBS air time even if only one candidate accepts the invitation:

Dear Candidate,  

The weekly PBS television broadcasts NOW on PBS and NOVA, the PBS science series, along with Public Television Stations KOPB (Portland, OR), WNET (New York) and WGBH (Boston), together with Science Debate 2008, representing the National Academy of Sciences, the National Academy of Engineering, the Institute of Medicine, the American Association for the Advancement of Science, and the Council on Competitiveness would like to invite you to participate in Is America Losing its Competitive Edge? A Presidential Debate on the role of Science in America's Future, a nationally televised event currently being planned for Portland State University, Portland, Oregon on the evening of Friday, May 2, May 9, or May 16.

We will broadcast even if only one candidate confirms, and we will publicize who confirmed first, so this could be a major win for your candidate with these communities both nationally and in Oregon, whose economy is dominated by the tech industry and whose largest employer is Intel, whose Chairman is one of the supporters of this initiative.

The moderator for the event will be David Brancaccio, the host of NOW on PBS, with a panel of internationally recognized scientists selected by the organizers, Science Debate 2008.

The leading organizer, screenwriter Shawn Lawrence Otto, began touting this idea last year, on the liberal website Salon, for one. But PBS producers only jumped on the bandwagon after the Republican race wound down: the NOVA crew joined the effort on February 25, and NOW on March 7.  

—Tim Graham is Director of Media Analysis at the Media Research Center.