Gallup’s daily presidential tracking poll has been a bit of a roller coaster ride in the last two weeks, with his lead over Hillary Clinton growing to 11 percent on Monday, but narrowing to just 3 percent by yesterday.

Monday’s 11 percent lead was the largest it has been in the campaign to date.

Gallup suggests that Obama’s drop to a 47 to 44 percent lead over Clinton may be attributed to the Wednesday night debate in Philadelphia: “The initial indications are that Obama may have been hurt by the debate, which was noted for its negative tone and focus on the candidates’ recent ‘gaffes…'”

That is at odds with other polls released today, that showed Clinton slipping after the debate. And, Gallup’s findings on a potential matchups with John McCain are at odds with today’s AP/Yahoo poll. That one showed McCain with a non-statistically-significant edge over Obama and Clinton. The Gallup poll had Clinton leading McCain, 46 to 44 percent, while Obama had a smaller lead, 45 to 44 percent, also within the margin of error.

The margin of error was plus or minus 2 percent.