America is awash in conspiratorial stupidity.

A new Rasmussen Reports national telephone survey finds that just 45% of American Adults reject as false the theory that President John F. Kennedy was assassinated by more than one shooter. Thirty-two percent (32%) believe more than one shooter was involved in the 1963 assassination in Dallas, and another 23% are undecided. (To see survey question wording, click here.)

Last November, on the 50th anniversary of the assassination, 36% of adults said Kennedy was the victim of a lone gunman, but just as many (37%) said he was the victim of a larger conspiracy.

One-in-four adults (24%) are convinced that the U.S. government knew in advance about the September 11, 2001 terrorist attacks and did nothing to stop them, and 19% more are not sure. Only 57% say that conspiracy theory is false.

Just as many (23%) say the theory that Obama is not an American citizen is true, with another 17% who aren’t sure. Sixty percent (60%) reject that theory as false.

I hope you’re sitting down for this one, because it’s a real jaw dropper:

Forty-one percent (41%) of Republicans believe Obama is not an American citizen, compared to 21% of unaffiliateds and 11% of Democrats. Just over 20% of Republicans and unaffiliated adults also are not sure, but only seven percent (7%) of those in the president’s party share that doubt.

Head…desk.

More: Have We Got a Conspiracy for You - 9/11? JFK? Obama’s Citizenship? - Rasmussen ReportsTM