Portman: Romney 'refreshing' in agreeing with Obama

"I thought when Gov. Romney did that, it was refreshing for a lot of undecided voters who are tired of the attacks back and forth, and the politics," Portman told CNN. "Look when Gov. Romney thought that the president was right, he said so."

But, Portman said, Romney was looking to also emphasize that he did not believe the president's handling of international relations was comprehensive enough.

"He also made it clear, by the way, that although he supported the drone attacks, he supported going after bin Laden, that that was not sufficient," Portman said. "And that's when he said we cannot kill our way out of these problems, we need to provide a vision and a strategy for the future that deals with the underlying problems here of Islamic extremism, and the spread of it."

Portman also looked to paint differences between Obama and Romney on issues such as the American withdrawal from Afghanistan, saying the candidates broke on "how you communicate it."

"So I think what you saw last night was, you know, frankly Gov. Romney saying, 'Look, all along I believed we ought to get out of Afghanistan. We ought to do it in a way, though, that is consistent with what our commanders on the ground think we ought to go in terms of the time frame,' " Portman said.