Vis instapundit we find this countering poll from the-fix.
Two weeks of Washington Post-ABC News tracking poll interviews find 84 percent of likely voters who supported Obama in 2008 support him this year, while 13 percent say they are switching to Romney and 3 percent are backing others or haven’t made up their mind yet.
Some basic math:
Obama winning percentage in 2008 52.9% * .84 = 44.43% with 1.5% undecided. With 6.87% of the 2008 vote shifting to Romney. With Republican enthusiasm at an all time high, Republican voter registration up, and an at least somewhat disillusioned Democrat party where is Obama going to find enough new voters to make up the gap?