"Joe Biden is going to be Joe Biden and that would have been true whether he was doing this after a different debate last week or not," said Van Hollen on CNN's "The Situation Room with Wolf Blitzer."
“I think it’s fair to say I was just too polite,” Obama said in a phone interview with the "Tom Joyner Morning Show."
Van Hollen, who served as a stand-in for GOP vice-presidential nominee Rep. Paul Ryan (Wis.) during debate preparations, praised Biden as a "fighter for the middle class."
"He feels it in his gut and, even more importantly, the policies that he and the president stand for will help the middle class, which is stark contrast to the Romney-Ryan plan, and so I think the nation is in for a very good discussion tonight," he said.
The Maryland representative said that Ryan is most vulnerable when it comes to "translating his budget and the impact that it has on real people."
He claimed that Ryan's policies would hurt seniors and provide tax breaks at the expense of the middle class.
However, he admitted that the Republican vice presidential nominee is "very quick on his feet."
"The question tonight is whether Paul Ryan will really level with the American people about the impact his budget will have on middle-class families, on seniors, or whether he's going to do what Mitt Romney did the other night, which is just try an run away from the Romney-Ryan plan," Van Hollen said.