TO read the headlines, intelligent design as a challenge to evolution seems to be building momentum.

In Kansas last month, the board of education voted that students should be exposed to critiques of evolution like intelligent design. At a trial of the Dover, Pa., school board that ended last month, two of the movement's leading academics presented their ideas to a courtroom filled with spectators and reporters from around the world. President Bush endorsed teaching "both sides" of the debate -- a position that polls show is popular. And Pope Benedict XVI weighed in recently, declaring the universe an "intelligent project."

Intelligent design posits that the complexity of biological life is itself evidence of a higher being at work. As a political cause, the idea has gained currency, and for good reason. The movement was intended to be a "big tent" that would attract everyone from biblical creationists who regard the Book of Genesis as literal truth to academics who believe that secular universities are hostile to faith. The slogan, "Teach the controversy," has simple appeal in a democracy.

Behind the headlines, however, intelligent design as a field of inquiry is failing to gain the traction its supporters had hoped for. It has gained little support among the academics who should have been its natural allies. And if the intelligent design proponents lose the case in Dover, there could be serious consequences for the movement's credibility.