WASHINGTON — Capping a year of last-minute, half-loaf legislation, the Senate voted overwhelmingly on Saturday to extend a payroll tax cut for only two months, with the chamber’s leaders and the White House proclaiming victory, even as they punted into the new year the issue of how to further extend the tax cut and unemployment benefits.

In an unusual Saturday vote, the Senate approved by an 89-to-10 vote a $33 billion package that would extend a payroll-tax holiday for millions of American workers, extend unemployment benefits and avoid cuts in payments to doctors who accept Medicare. The measure would be effective through February, when Congress could again be locked in battle over whether and how to extend those provisions.

The legislation — should it get through the House — mirrors a series of 11th-hour deals devised by the 112th Congress that appeared to solve an impending crisis, but simply pushed the issues forward.

But House passage next week was thrown into serious doubt on Saturday afternoon, when a number of rank-and-file Republicans objected in a conference call with Speaker John A. Boehner, who tried to persuade them that it was good for their party, particularly the provision that would speed the decision process for construction of an oil pipeline from Canada to the Gulf Coast known as Keystone XL. Just a week ago, President Obama had threatened to veto that provision.