(CBS News) With the conventions now behind us, President Barack Obama and challenger Mitt Romney have sharpened their attacks and their focus on the middle class.
While campaigning in the key state of Florida on Sunday, President Obama took aim at Romney and his running mate, insisting their policies would favor the rich at the expense of the middle class.
"They couldn't answer questions about how they'd pay for $5 trillion in tax cuts and $2 trillion in new defense spending without raising taxes on the middle class," Mr. Obama said.
It's a theme the president and the vice president are hammering. Also Sunday, in Ohio -- another key state - Vice President Joe Biden questioned Romney's priorities.
"Giving these massive tax cuts to the wealthy -- guess who gets the bill: you," Biden said.
The Obama campaign is trying to portray Romney as out of touch, in the pocket of big business, but in an interview on NBC's "Meet the Press," Romney offered a forceful defense.
"Contrary to what the Democrats are saying, I'm not going to increase the tax burden on middle income families. It would be absolutely wrong to do that," Romney said.
Accusing Democrats of playing politics, he also flatly denied he would give the wealthy a tax break.
"We're not going to have high-income people pay less of the tax burden than they pay today. That's not going to happen. High-income taxpayers are going to have fewer deductions and exemptions," Romney said.
But democrats say the math doesn't add up: If Romney refuses to raise taxes, how does he pay for it all without cuts, especially to the defense spending?
Romney said his tax policies would encourage hiring and grow the economy, and vowed to balance the budget by the end of his second term.
He also criticized the president and Republican leaders for agreeing to mandatory across-the-board spending cuts, including defense, if both sides can't strike a deficit reduction deal by the end of the year.
"That's a big mistake. I thought it was a mistake on the part of the White House to propose it. I think it was a mistake for Republicans to go along with it," Romney said.
Romney said the president was more to blame, but of course one of those Republican leaders who agreed to the deal was his own running mate, Paul Ryan.