Calling Mitt Romney’s performance historic, Gallup noted Monday that in the three days of polling since Thursday's presidential debate the GOP challenger has erased a five-point deficit and is in a 47-47 tie with President Barack Obama.Gallup, as other polls have shown, found that Americans, by a historic margin, overwhelmingly believe Romney won the first debate by a margin of 72 to 20. Even Democrats, by a margin of 49 to 39 percent, believe Obama was bested.“Across all of the various debate-reaction polls Gallup has conducted, Romney's 52-point win is the largest Gallup has measured,” Gallup’s Jeffrey Jones noted. “The prior largest margin was 42 points for Bill Clinton over George H.W. Bush in the 1992 town hall debate.”However, the Gallup presidential tracking poll generally reports on a seven-day average, not three, and in that metric Obama is still ahead 49 to 46.“Even on this basis, the race has become somewhat more competitive compared with before the first debate,” Jones wrote. “Obama held four- to six-point leads in Gallup's seven-day tracking results in the eight days prior to the Oct. 3 debate.”Nonetheless, Gallup called the movement “significant” given both the closeness of the race and “the fact that debates rarely transform presidential election races.” Gallup also pointed out that the “generally positive unemployment report released on Friday may serve to blunt some of Romney's post-debate momentum.”With that in mind, the Rasmussen Reports daily Presidential Tracking Poll for Monday, which is on a three-day cycle, had the two candidates tied at 48 percent. In three polling reports prior to the debate, Rasmussen showed Obama up by two. In two reports after the debate, Romney had jumped ahead by two.“While there have been modest swings in recent months that have favored one candidate over the other, the overall picture is of a race that is both stable and very close,” Rasmussen wrote. “Over the past 100 days of tracking, Romney and Obama have been within two points of each other 72 times. Additionally, on 89 of those 100 days, the candidates have been within three points of each other. That is exceedingly close in a poll with a three percentage-point margin of error.”