Maryland Gov. Martin O’Malley (D), a regular surrogate for President Obama, addresses the Democratic National Convention in Charlotte last month. (AP Photo/J. Scott Applewhite)

In an early morning appearance on CNN’s “Starting Point” from Denver, the site of the debate, O’Malley (D) knocked the Republican challenger for putting forward no new ideas on creating jobs and declining to detail how he would pay for his tax plans.

“He tells us we can all eat cake and lose weight, ‘Trust me, I’ve got a secret plan behind door No. 2,’” said O’Malley, the chairman of the Democratic Governors Association. “That’s going to wear old with intelligent voters over the course of these next debates.”

Republican presidential nominee Mitt Romney and President Obama shake hands during the first presidential debate at the University of Denver. (AP Photo/Charlie Neibergall)

“The president didn’t bring his ‘A’ game,” Carville said.

Asked about that comment, O’Malley replied: “This was the first day that was not a disastrous and miserable day for the Romney campaign in many, many weeks.”

O’Malley, who won re-election in 2010, added: “I’ve been in these debates, and always it seems the challenger has an edge in that very first debate.”