This might be more useful:
Gallup Poll: Education, Race, Income and Political Affiliation
Pretty much split down the middle on education until you get to post-graduate where Obama has a 13 point advantage.
I think that raises an interesting "chicken or egg" question. Do those with post-grad degrees favor Obama because they're more intelligent and more intelligent people just favor Obama? Do the universities tend toward a Democrat position because they're more intelligent, or are they a product of a largely Democratic/liberal university system and the system attracts its own? Essentially are the universities predominantly Democratic and therefore the people who thrive in that environment (i.e. go on to obtain a post-grad degree) tend to be Democrats also?
Obviously each side would like to claim one position or the other. I think simply looking at the poll and concluding that "Smarter people favor Obama" is an oversimplification - it deserves some more thought.