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Speaking to me this morning on "This Week," Ohio Sen. Rob Portman said GOP presidential nominee Mitt Romney could "probably" win the White House without a victory in the Buckeye State, a feat that no other Republican has accomplished.

"Look, you can probably win the presidency without Ohio, but I wouldn't want to take the risk. No Republican has. And we're doing great in Ohio," Portman said. "If you look at the average of all the polls, it's about dead-even in Ohio right now. And importantly, the momentum's on our side. It's been terrific."

Portman was responding to a recent poll I asked him about that showed Romney trailing the president by six points in Ohio.

I also asked Portman - who is helping prep Romney by playing Obama in mock debates - what we should expect on Tuesday, during the second presidential debate. He predicted that Obama would come out "swinging."

"I think President Obama is gonna come out swinging. I think he's gonna have to compensate for a poor first debate, and I think that'll be consistent with what they've been doing this whole campaign, Jake, which is running a highly negative ad campaign," Portman said. "They've spent hundreds of millions of dollars around the country, including a lot in Ohio, mischaracterizing Governor Romney's positions and misrepresenting him. And I think you'll see that again at the debate on Tuesday night."

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