"I've spent a lot if time with Gov. Romney. I think that he has a strong understanding of foreign policy, and he does not have a Cold War view toward Russia," Ayotte told a conference on Russian democracy, according to CNN.

Romney raised eyebrows when he described Russia as the top "geopolitical foe" of the United States in March, and officials in the Obama administration criticized the Republican hopeful as having an outdated foreign policy.

“I think Romney’s social policy is right out of the ’50s, seriously, right out of the ’50s. I think his foreign policy is right out of the Cold War and his economic policy is just doubling down on the eight years the last administration put us in this god-awful mess in the first place," Vice President Biden said at a campaign stop in Dubuque, Iowa, Wednesday.

The comment also drew condemnation from Russia's then-President Dmitry Medvedev, who suggested candidates should "use their head."

"It is now 2012, not the mid-1970s," Medvedev said.

But Ayotte, who serves on the Senate Armed Services Committee, defended Romney, saying the Obama administration had erred in its handling of Russia.

"[Romney], like me, very, very much disagrees with the accommodations we have toward Vladimir Putin," Ayotte said. "Vladimir Putin is an autocrat, he's someone we shouldn't be supporting, and I think this administration has been much too accommodating toward Mr. Putin."

She also heralded the campaign's foreign policy team.

"He really has very strong foreign policy advisers, and many of our great leaders have served as governors first, including Ronald Reagan," said Ayotte. "I know who his foreign policy team is, he's got the very best advisers on foreign policy, and the other thing I know about Gov. Romney is he's someone who does his homework, he's very thoughtful, and he will reach out to leaders in Congress."

Romney himself defended his comments in an interview last week with Fox News Radio, although he softened his tone.

"Of course we're not enemies. We're not fighting each other, there's no Cold War," Romney said. "But Russia is a geopolitical opponent, and in that regard I think we've seen very clearly that they continue to pursue a course which is antithetical to the interests of our nation."