"Everything is sketchy," Biden said.
President Barack Obama "had a great debate," Biden said, "and I expect you'll see another great one next Monday" when the two presidential candidates meet for a third and final debate.
Biden also addressed questions over the Obama administration's response to requests for increased security at the U.S. consulate in Benghazi, Libya. The U.S. ambassador and three other Americans were killed there last month. At last week's vice presidential debate, Biden had asserted "we weren't told" about the requests. But a State Department official had acknowledged during congressional testimony receiving the request.
Biden, who spoke in a round of television interviews broadcast Wednesday, said he meant that he and Obama were not personally aware of those requests. "It never got to us," Biden said.
The vice president also accused Romney of trying to "politicize a tragedy" by continuing to make the Benghazi attack an issue in the campaign.
But Republican vice presidential candidate Paul Ryan said it's a legitimate national security issue.
"We learn more troubling facts by the day, and so that's why need to get to the bottom of this, to get answers so that we can prevent something like this from ever happening again," he told CBS' "This Morning."