In second debate, Obama faces challenges on key issues

U.S. President Barack Obama greets supporters at his campaign office in Williamsburg, Virginia, October 14, 2012. REUTERS/Jonathan Ernst

WASHINGTON (Reuters) - Losing ground to Republican Mitt Romney on a host of issues, President Barack Obama faces a serious challenge to put his re-election bid back on track when the two men face off on Tuesday in their second debate.

Obama's passive performance in their first debate two weeks ago and Romney's subsequent surge have raised expectations for a more fiery encounter at New York's Hofstra University.