Ben Smith rounds up some survey data:
22 percent believe President Bush knew about the 9/11 attacks in advance.
30 percent believe Saddam had weapons of mass destruction.
23 percent believe they’ve been in the presence of a ghost.
18 percent believe the sun revolves around the Earth.
Hilzoy comments here. Maybe ten percent of Americans believing Obama is a Muslim isn’t so high after all.
The Dish 