President Obama is warning of dire consequences if Congress does not extend payroll tax cuts.
At a campaign-style rally in Scranton, Pa., he said failure by Republican lawmakers to do so would deliver a "massive blow to the economy."
The president called on the GOP to help middle class Americans by raising taxes for the wealthy.
"Are you going to cut taxes for the middle class and those who are trying to get into the middle class, or are you going to protect massive tax breaks for millionaires and billionaires?" he challenged.
"Are you going to ask a few hundred thousand people who have done very, very well to do their fair share or are you going to raise taxes for hundreds of millions of people across the country?" he asked.
Republicans say they support renewing the tax cut but reject new taxes to pay for it.
"The Democrats can say they just want some people to pay a little bit more to cover this or that dubious proposal," Senate Republican leader Mitch McConnell said.
"Think about that," he added. "The Democrats' response to the jobs crisis we're in right now is to raise taxes on those who create jobs. This isn't just counterproductive. It's absurd."
Instead, Republicans want to extend an existing pay freeze for government workers through 2015.