The U.S. economy added more jobs in January than in any month since early last year, pushing down the unemployment rate to a level not seen since President Barack Obama's first full month in office.

Employers added 243,000 jobs last month, the Labor Department said Friday, notching gains across a wide swath of the economy. That marked the fastest pace of job growth since April and brought the unemployment rate down to 8.3%, from December's 8.5%—the fifth consecutive monthly decline.

The healthier-than-anticipated labor picture propelled stock prices higher from the opening bell, extending a rally that has surprised many investors with its durability. The Dow Jones Industrial Average jumped 156.82 points, or 1.2%, to 12862.23 on Friday, its highest close since May 2008. The Nasdaq Composite Index, meanwhile, hit its highest close since December 2000, gaining 1.6% to close at 2905.66.

The report was seized on by both sides in the presidential campaign, which is focused heavily on how to get the economy growing rapidly to bring down unemployment. Democrats pointed to the job gains as evidence that the president's policies are working, while Republicans countered that those same policies have prolonged the downturn and kept joblessness high.

The employment report built on several months of data that have soothed concerns among investors that the U.S. economy would be dragged down by Europe's debt-induced woes. If the labor market's good news continues, it could help offset worries about the health of corporate earnings. Many companies' fourth-quarter earnings reports reflect profit margins coming under pressure.