(Reuters) - Republican challenger Mitt Romney has extended his lead over President Barack Obama to 3 percentage points, according to a Reuters/Ipsos tracking poll released on Thursday, ahead of a high-stakes debate between the two candidates' running mates.

Romney now leads the Democrat by 47 percent to 44 percent among likely voters in the online poll, with less than a month before the November 6 election. The Republican had a one-point lead over Obama in survey results on Wednesday, his first in more than a month.

Romney has been enjoying one of his best runs of the campaign after handily winning the first presidential debate last week, partially due to Obama's passive performance in that contest.

"The momentum is in Romney's direction right now," Ipsos pollster Julia Clark said...