There have been many news reports over the past few years debunking the rumor that Obama is a Muslim. Nevertheless, the right-wing media continues to push the myth. These fringe views aren’t rejected by influential conservatives, but often embraced, and therefore picked up in mainstream discourse and media. Saying that he needs to publicly change his habits of worship in order to appease people is like saying he needs to roll around in big piles of money to show he isn’t a socialist.
And in the end, there will always be people who can’t be convinced of mainstream positions. Twenty-one percent of the public believes in witches, 41 percent believe in ESP, and 34 percent are convinced that “houses can be haunted.”
Things that are mainstream aren't necessarily true, and plenty of thoroughly mainstream views in a majority Christian country seem as "nutty" to nonbelievers as the apparent non-mainstream beliefs she listed. Atheism is obviously a fringe belief in the US, as is belief in the Islamic religion.
The point is there's a difference between beliefs about things which are basically verified or verifiable and beliefs which are in the realm of faith. Yes it's possible Obama is secretly a Muslim, but all available facts (remember that Reverend Wright stuff?) suggest otherwise. The virgin birth and divinity of Jesus and the existence of ghosts are, as far as I know, not exactly verified and as of yet not verifiable. Still people are free to believe them and I can't say they're wrong, I can only say I doubt they're right.
..adding that while I'm not religious despite occasional accusations to the contrary I'm not anti-religion. Most of us believe in things which don't necessarily have a strong factual basis, and most of us probably construct some unsupported paradigm to try to make sense of the universe and our place in it.