WASHINGTON — The Senate’s top Republican on Thursday urged the GOP-led House to pass a short-term renewal of payroll tax cuts and break an impasse that threatens all workers with a Jan. 1 tax increase.

Within hours, a House Republican freshman broke ranks and agreed, signaling that fierce pressure from almost every corner of the Republican Party had begun to crack conservative opposition to a short-term fix.

“This isn’t about proving a point,” said Rep. Sean Duffy, R-Wis. “Middle class families deserve a Congress that will rise above the squabbling and ensure their taxes don’t go up right after Christmas.”

He called on his own Republican leaders to take up a two-month extension of the cuts, days after the House rejected such a plan passed by the Senate and held out instead for a one-year renewal

The statement suggested that GOP Leader Mitch McConnell’s plan may have started to break down a deadlock between House Republicans and Democrats controlling the Senate that had split House and Senate Republicans, too.

McConnell urged House Republicans to pass a new short-term extension while calling on Senate Majority Leader Harry Reid, D-Nev., to appoint negotiators on the separate House measure that would bring a year-long renewal of the payroll tax and jobless benefits.