As I mentioned last week, I got to spend some time in Tampa with some Texas 'birthers'. As TPM shows, understanding exactly what they believe is a little complicated. Like with 9/11 'truthers', they fall into different, sometimes overlapping camps, and holding multiple, contradictory beliefs in one's head is definitely allowed.
Of the 24% of the population in the 'birther' category, one interesting thing to note is that more Americans seem to think Obama was born in Indonesia (10%) than Kenya (7%), which suggests not only that a frighteningly large number of Americans are birthers but that they have a shockingly low level of basic 'birther' literacy. As you know, according to orthodox 'birther' theory, Obama was born in Kenya.
Even better, 6% fully concede that Obama was born in Hawaii. They just don't believe Hawaii is part of the United States.
I was lucky enough to be sitting for a week next to a gentleman, who, as far as I could discern, believed something akin to that Hawaii stuff.
Note: I refuse to use the word "theory", to describe these beliefs, as it is a debasement (though now a common one), of the original meaning of the word.
"a coherent group of general propositions used as principles of explanation for a class of phenomena: Einstein's theory of relativity."