I'm fairly certain that the "rumor" was run often enough to have been eliminated for him to win as Guv.
It is somewhat reminiscent of the Bush Nat'l. Guard rumors. The media had wrung every drop out of them before he even became governor, but that didn't stop them from trying and trying again.
In answer to the question about the MSM pursuing the Obama rumors: Of course not, Obama's a democrat. Democrats claim no morals and, so, are not to be labeled as hypocrites when they display it.