Tom DeLay wants Obama to prove a negative:

Former House Republican Leader Tom DeLay (Texas) called Barack Obama a "Marxist" on the Mike Gallagher radio show Thursday.

Explaining that Obama clinching the Democratic nomination is a good thing for John McCain, DeLay said Obama's "weakness" is that "nobody knows him."

"And if McCain does not define him as what he is -- hey, I have said publicly, and I will again, that unless he proves me wrong, he is a Marxist," DeLay said.

The radio host agreed with DeLay, who is facing money laundering charges, saying Obama is "desperately trying to cover up what seems to be the kind of old school Marxist radical liberal failed ideology."

"Absolutely," DeLay said. "No doubt about it."

Um, this is not the message Republicans want to be putting out on Obama. Good ol' fashioned liberal would probably suffice.