It won't win him any votes from Hillary's camp (less educated, white collar whites) but it will shore up his support base (educated whites).
It was a very unpolitical move, and that's probably why it was so refreshing.
I've been over this uneducated vs educated argument before, Hillary has significant support from educated voters. His support base isn't educated whites, its an unorthodox coalition of african americans, youth voters of all educational backgrounds, and some independents. Its true that on average Obama gets slightly more of the PH.D, MA, and BS/BA crowd in states he wins (he has been known to win 60% among educated people, whereas she wins by 50% margins in states she wins typically), but Hillary has pulled strongly in states like Texas, California, New York (and most the "big states") among the educated crowds and he hasn't won a signifcant majority there.
To reduce this primary to saying all Hillary's base is uneducated and Obama's support is educated is a bias that isn't true.
Personally I only have a college degree (diploma in Canada) and have 80 credit hours, and I actually hope to finish out a bachelors degree in Ontario eventually... But I consider myself among the better-educated crowd (I earned 60 of those hours in a university setting) and I have typically supported Hillary. But I also like Obama, and this primary and caucus season has drained my emotions. I dislike seeing two capable people tear EACH OTHER apart. Obama's team has been playing so many dirty tricks its not just the Hillary team that has fought hard. Its not the candidates themselves as much as its the campaign and/or supporters of each.
I wished the support teams from both campaigns would realize how similar these candidates are. I mean policy-wise they are nearly identical, the subtle differences in policy they argue over is a joke. The biggest differences I've noticed are foreign policy where Obama promises to meet with leaders in Iran or the like without really waiting.
Their pull-out strategy is the same, their health policy is almost identical and the changes Congress will make are bigger than the differences in the plans they propose. Their energy independence policy is similar, their stance on equality and civil rights is similar. Neither candidate supports gay marriage, but stakes a claim to make the debate more civil.
What this campaign has become is a fight over personality and generation.