Following last week's debate, President Obama has lost his five-point lead in Gallup's tracking poll of registered voters. In the first three days of polling since the debate, Obama and Mitt Romney are tied at 47 percent each. 

In the poll's seven-day rolling average Obama still has a three-point edge, but that includes three days before the debate. Clearly, the race has narrowed slightly but significantly in Gallup polling since. 

Debate-watchers agreed that Romney beat Obama by a 72 to 20 percent margin. Even Democrats agreed that Romney did better than Obama, 49 to 39 percent. 

Romney's 52-point debate win is the largest Gallup has ever recorded. The closest was a 1992 town hall debate, in which voters agreed that Bill Clinton beat George H.W. Bush by a 42-point margin.

The tracking poll results come from a survey of 1,387 registered voters with a margin of error of plus-or-minus 3 percentage points. The debate results come from a poll of 749 debate watchers; the margin of error is plus-or-minus 4 points.

A Politico/GWU poll released Monday found Romney and Obama tied among likely voters, with Romney leading among those extremely likely to vote. But most of that survey was conducted before last week's debate and thus does not reflect any new momentum for the GOP candidate.