The House of Representatives voted Thursday to approve the cuts for the middle class and the poor, with most Democrats voting yes and most Republicans voting no.
Democrats expressed their disdain for an across-the-board extension, charging that Republicans were giving the rich help they didn't need.
Most Democrats, and President Barack Obama, favor an extension of the cuts only for individuals earning less than $200,000 and couples making less than $250,000. Republicans, and some moderate Democrats, want all the cuts extended, saying that raising taxes during an economic slump would be disastrous.
If the cuts for the wealthy aren't extended, the two top rates, now 33 percent and 35 percent, would go back to pre-Bush era levels of 36 percent and 39.6 percent.
"It's a question of who you're going to help," said Sen. Mark Begich, D-Alaska. "We're going to help the small business owners. We're going to help the middle class."
Obama said Saturday that the middle-class tax cuts were being held hostage by the Republicans.
"I am very disappointed that the Senate is not going to pass legislation that has already passed in the House of Representatives that would make the middle-class tax cuts permanent," he said. "Those provisions should have passed."
Republicans countered that the Saturday votes were little more than a political show, and now that they're done, lawmakers can get on with serious negotiations.
"It became apparent the second time we met," said Sen. Jon Kyl, R-Ariz., one of the negotiators, "that actually there wasn't going to be any bipartisan negotiations to reach a decision until there had been a political catharsis on the Democratic side."