Most people are wrong about Obama's religion

How does the media know Obama is not a Muslim? According to a recent CNN /ORC poll only 39% of Americans think he is a Protestant / Christian meaning that 61% them either believe otherwise or have no opinion. Among whites 33% think Obama is a Muslim and only 36% believe he is a Protestant which puts it within the 3.5% margin of error. So why should Donald Trump wade into the controversy?

34. Do you happen to know what religion Barack Obama is? Is he Protestant, Catholic, Jewish, Mormon, Muslim, something else, or not religious? (RANDOM ORDER) Sept. 4-8 2015

Protestant/Christian	39%
Catholic	4%
Jewish	1%
Mormon/Church of Latter Day Saints	2%
Muslim/Islam/Islamic	29%
Something else	1%
Not religious	11%
No opinion	14%