Joe Biden did everything President Barack Obama did not last week, and a good bit more. 

The vice president dominated the spotlight in the only debate between himself and Rep. Paul Ryan (R-Wis.), charging at Republican Mitt Romney's running mate from the get-go and bombarding him with a flurry of eye rolls, interjections and accusations.

What it accomplished among undecided voters, if anything, is hard to tell and will take days to sort out. Two instant surveys of Americans watching the debate -- one by CBS, one by CNN -- showed mixed results. But since vice presidential debates often have a negligible impact on the overall race anyway, Biden's sometimes over-the-top performance probably accomplished what he appeared intent on doing: rallying the Democratic base after Obama's woeful debate performance last week.

Obama, at least, was cheered by the offensive. See what the President said;