Gallup: “The vast majority of U.S. voters are remaining consistent in their voting preferences between 2008 and 2012, be it for Barack Obama or the Republican presidential candidate. But loyalty to Obama is slightly less than loyalty to the Republican candidates, resulting in a more competitive race at this point than in the final 2008 results.”

“The 11% of 2008 Obama or McCain voters who have switched to supporting the other party’s candidate or are undecided at this point is not a relatively large group. But it is a group that could potentially be persuaded between now and Election Day, and thus could be crucial in deciding the outcome.”
Taegan Goddard’s Political Wire