The U.S. unemployment rate dropped to a near four-year low of 7.8 percent in September, a potential boost to President Barack Obama's re-election bid.

The Labor Department said on Friday that the unemployment rate, a key focus in the racefor the White House, dropped by 0.3 percentage point to its lowest point since January 2009.

A survey of households from which the jobless rate is derived showed 873,000 job gains last month, the most since June 1983. The drop in unemployment came even as Americans moved back into the labor force to resume the hunt for work. The workforce had shrunk in the prior two months. 

The household survey is volatile. A survey of business establishments showed employers added 114,000 jobs to their payrolls last month, a touch above economists' expectations for 113,000 jobs. Employment for July and August was revised to show 86,000 more jobs created than previous reported. Read more;