Congressional negotiations over a bill extending a payroll tax cut and unemployment benefits can begin as soon the Senate rejects a version the House approved despite a White House veto threat, the Senate's top Democrat said Wednesday.

Republicans are girding to push a bill through the House that would continue a payroll tax cut for 160 million workers, but has drawn White House and Democratic objections because it would also force work on a controversial oil pipeline.

House Republicans unveiled a bill Friday renewing the Social Security payroll tax cut and extending but trimming unemployment benefits but barreled toward a showdown with President Barack Obama by including language jumpstarting work on a controversial oil pipeline.

House Speaker John Boehner said Thursday he's confident that congressional Republicans are ready to move ahead with legislation that would continue a payroll tax cut.

Congress' failed deficit-cutting supercommittee has faded away, but a stack of expensive economic problems facing lawmakers has not.

Failure by Congress' debt-cutting supercommittee to recommend $1.2 trillion in savings by Wednesday is supposed to automatically trigger spending cuts in the same amount to accomplish that job.

Congressional Democrats and Republicans rallied on a rare patch of common ground Wednesday, moving toward passage of legislation helping unemployed veterans and government contractors.

Members of Congress' deficit-reduction supercommittee face daily pressure from groups defending programs like Social Security, veterans benefits and defense spending from cuts. This week will offer something different: Millionaires insisting that their own taxes be raised.