Gallup has sorted through its polling to further document why there has been such a divide among Democrats along the lines of education in terms of backing either Hillary Clinton or Barack Obama, but in the end, can’t find enough evidence to support a good explanation for it.

Based on data collected April 1-7, Gallup reports that Clinton leads Obama by 50 percent to 43 percent among voters who have a high school education or less. But as you go up the education ladder, Obama’s advantage steadily increases: 53 percent to 40 percent over Clinton among voters with some college, 59 percent to 35 percent among college graduates, and 64 percent to 30 percent among those with postgraduate studies. Black Democrats support Obama across all education levels.

Gallup considers various theories such as the idea that less-educated voters are also less receptive to a black candidate. But it notes that in a poll it did last year, there was not much difference between highly and less educated voters on the question of whether they would vote for a “generally well-qualified person for president who happened to be black.” Gallup also did not find much evidence that the Jeremiah Wright controversy caused any backlash among less educated voters. It also rejected name recognition as a possible factor since both candidates have wide name recognition. In the end, the Gallup people mused: ” It could be that less well-educated voters are simply more comfortable with candidates who have been around for a long time (Clinton in this year’s race), while Democratic voters with higher education levels are more comfortable supporting someone who is new on the scene.”