Obama repeated his past criticism that Romney's tax plan doesn't add up, saying "when he's asked how are you going to do it, which deductions, which loopholes are you going to close, he can't tell you."
"You're going to be paying for it," Obama said of middle class taxpayers. "You're going to lose some deductions, and you can't buy the sales pitch. Nobody who's looked at it that's serious actually believes it adds up."
Romney, meanwhile, repeatedly insisted his plan won't raise taxes for middle class Americans but also won't raise or lower the tax burden on the wealthy, in contrast to Obama's proposal to let tax rates on the top 2% of wage earners return to higher tax rates from the Clinton era.
The president needed a strong debate to try to blunt Romney's rise in the polls after their first showdown. The most recent CNN "poll of polls" -- an aggregate of the latest major surveys -- showed Romney with a slight edge nationally at 48%-47%.
In the battleground states considered up-for-grabs, polls show Romney has narrowed Obama's lead or caught the president.