McCain, echoing other Republicans and political pundits, said the debate was a decisive win for Romney.
"Last night was so bad if it had been a fight, they would have stopped it," McCain said.
But McCain also warned that Obama was not done, and said there was still a strong possibility that he would dominate in the next two presidential debates of the election cycle.
"This president is very smart. He's very intelligent. He's an excellent speaker. I think he was fairly rusty," McCain said. "He has had four years relatively unchallenged in the things that he has said. Mitt went through a very tough primary, as we all know. I think that showed up last night. I would not underestimate the president of the United States in the next couple of debates, and I don't think Mitt will either."
Other members of Romney's campaign hailed Romney's performance on Wednesday. Romney adviser Ed Gillespie said the debate was a "dynamic shift in the campaign."
Meanwhile, Obama campaign senior adviser David Axelrod said that moving forward, the Obama campaign would more aggressively challenge Romney on inconsistent statements.
"You know, you can't tell the American people up is down and down is up and ignore your history and ignore your statements," Axelrod said Thursday.