The five-year old video showing President Barack Obama talking bluntly about race, Hurricane Katrina and the Rev. Jeremiah Wright is a source of worry for a campaign that�s already on a knife�s edge over Wednesday night�s high-stakes debate in Denver and thinning leads in national polls.

Obama�s aides and top Democratic officials projected an air of nonchalance and nothing-to-see-here Tuesday night as Fox News and Tucker Carlson�s Daily Caller promoted the 2007 speech at Hampton University as a racial rant with the capacity to change the game. But the reelection campaign is concerned especially by the possibility of re-litigating Wright�s role in Obama�s life � a storyline long seen in Obamaland as among the most damaging to the president.

That�s made even stronger by the new focus on the tape coming at a key moment in the run-up to the debate � timing that could become a distraction for the campaign as the president prepares to take the stage.

The larger threat posed by the video isn�t its content � many of the statements Obama makes have been made by the president or other Democrats � but its capacity to stop the campaign�s accelerating momentum. Taken in combination with several other pre-debate problems for Obama � from tightening polls in Florida and Wisconsin and Vice President Joe Biden�s declaration Tuesday that the middle class has been �buried� over the last four years � the tape could be part of a movement that might make the race not the blowout many pundits have been predicting.

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