David Link understands Newt's game:
Gingrich is trying to morph Obama into San Francisco’s Gavin Newsom. Newsom, in fact, is the lawless politician Gingrich wishes Obama were, who not only refused to enforce California’s anti-gay marriage prohibition, he ostentatiously allowed people in his city to openly violate it. This was a politically savvy and profitable move for him (he is now California’s Lieutenant Governor) but it was an unapologetic violation of his legal duties, something the California Supreme Court made abundantly clear.
Obama is not Newsom. Newsom took what he believed to be a moral position, akin to civil disobedience. That is fine for individual citizens, but it is a bit more precarious for someone whose job is to administer the law.
Obama has either learned from Newsom’s escapade, or is relying on a different political instinct.