By Christopher S. Rugaber

AP Economics Writer

WASHINGTON (AP) — The U.S. job market is proving sturdier than expected at a time when the economy is under pressure from Washington gridlock and the threat of government spending cuts.

Employers added 157,000 jobs in January, and hiring was much stronger at the end of last year than the government had previously estimated.

The Labor Department’s estimated job gains for the final two months of 2012 — a period when the economy was being threatened by the fiscal cliff — rose from 161,000 to 247,000 for November and from 155,000 to 196,000 for December.

The mostly encouraging jobs report Friday included one negative sign: The unemployment rate rose to 7.9 percent from 7.8 percent in December. The rate is calculated from a survey of households, and more people in that survey said they were unemployed.

The monthly job gains are derived from a separate survey of employers.

The hiring picture over the past two years also looked stronger after the department’s annual revisions. The revisions showed that employers added an average of roughly 180,000 jobs a month in 2012 and 2011. That was up from previous estimates of about 150,000.

Other economic news Friday contributed to the stock rally. Manufacturing expanded at a much faster pace in January compared with December, a private survey found. And construction spending rose in December at a healthy pace.