I don’t know if pushing this is good or bad. Who was the guy who lost the election by sitting in a tank? People remember the oddest things in elections.
I don't think there's anything to push. In all honesty, I think that he's neither Muslim nor Christian. Like many other sophisticated elites, I'm sure he can appreciate certain aspects of religious culture. In a detached, intellectual way, of course. I'm certain he understands that, as a liberal politician, there are negative political ramifications to appearing as anything other than a semi-observant Christian. It just comes with the job.
This is my belief: Obama thinks that being Muslim is no more dangerous or relevant than believing in Santa Claus, and deeply resents having to pretend otherwise for the temporary appeasement of the unwashed redneck hordes he intends to command next January.
Beyond that, I doubt he thinks there's a spark of truth in Islam, Christianity, or any other religion. They're just cultural flavor to him. He went to a madrassa as a youth, and probably remembers Islam as cute, primitive and otherwise harmless. If he sides with Islam at all, it's only out of resentment for having to pretend he's Christian in order to advance his career.