Over at Concurring Opinions, Nate Oman has one possible answer:

[Cass] Sunstein writes of him: When he offers visionary approaches, he does so as a visionary minimalist--that is, as someone who attempts to accommodate, rather than to repudiate, the defining beliefs of most Americans. His reluctance to challenge people's deepest commitments might turn out to be what makes ambitious plans possible--notwithstanding the hopes of the far left and the cartoons of the far right.

He goes on to insist, "Above all, Obama's form of pragmatism is heavily empirical; he wants to know what will work."

So it turns out that Obama is a minimalist empiricist who believes in market-based approaches for pursuing progressive ends. In short, Obama is...Cass Sunstein.