Despite a busy holiday season that saw a gain of 200,000 jobs in December, some economists estimate a sluggish U.S. job market in the first month of 2012, as the positive effect of the shopping spree on the labor market eased off.

They expected only over 100,000 jobs were added in January and the unemployment rate could inch up to 8.6 percent.

As the holiday shopping season ended, as many as 40,000 couriers and messengers hired late last year were most likely to be left without a job in January, according to Heidi Shierholz, an economist at the Economic Policy Institute in Washington D.C.

Additionally, the construction sector also slowed down due to adverse weather conditions and the already weak building activity across the country.

"I think we're probably going to get somewhere in the range of 100,000 to 120, 000 jobs," Shierholz said.

The U.S. government is expected to release its latest job market numbers on Friday.

While the health sector is expected to see some growth, along with trading and manufacturing, they will be offset by the losses of jobs in state and local governments, she added.

"We're adding enough jobs to keep things from getting worse," said Shierholz. "But we are not adding enough to start digging our way out of the hole we are in."

The "hole" Shierholz refers to is the remaining labor market gap of over 10 million jobs, which was lost during the recession. Just to hold the unemployment rate steady, the U.S. economy needs to create 90,000 jobs a month.

But at the pace of December, a monthly addition of 200,000 jobs, it will take until 2019 for the U.S. job market to return to the pre-recession level. To get back to full employment in four years, the economy needs to add 320,000 jobs a month.

As it is now, the "minimal growth" in the labor force, which is "a sign of little confidence in the health of the job market," is worth noting, said economist Ryan Sweet of Moody's Analytics.

"Typically we wanted to see stronger labor force growth as the recovery matures," Sweet said, offering similar observation as Shierholz.

Sweet is even more conservative in his January estimates, predicting a non-farm payroll growth of 100,000.

"The labor market is improving but at a glacial pace," Sweet said. Temporary hiring by factories in December was unwinding in January, so a weaker employment is inevitable, he said.

One solution Sweet proposed is the extension of the payroll tax holiday until the end of 2012. The current payroll tax holiday is set to expire in February and the debate over the issue is creating too much uncertainty among business owners, he said.

"If they don't extend the payroll tax holiday, I think it will be potentially too much for the economy to adjust and that it would increase the odds of another recession," Sweet said.

Sweet also warned that the ongoing European crisis could also drag down the U.S. economy and stall the recovery. "Europe is already in recession and that' s going to reduce U.S. exports, which will hurt hiring," he said.

Sweet predicted the U.S. Federal Reserve will remain aggressive in the event of a job market slowdown. Should that slowdown happen, he said, the Fed will implement a third round of quantitative easing, by printing more money to circulate in the economy.

Shierholz called for a "substantial" stimulus package to generate more jobs and bring the unemployment down, saying it is the right fiscal policy.