WASHINGTON — President Obama isn’t talking about it, and neither is Mitt Romney. But come January, 163 million workers can expect to feel the pinch of a big tax increase regardless of who wins the election.

A temporary reduction in Social Security payroll taxes is due to expire at the end of the year and hardly anyone in Washington is pushing to extend it. Neither Obama nor Romney has proposed an extension, and it probably wouldn’t get through Congress anyway, with lawmakers in both parties down on the idea.