Polling companies routinely reported that one-quarter of Americans believed that former President Barrack Obama was Muslim. Using an experiment called the Implicit Association Test, we investigate whether individuals truly believed this misconception or simply expressed negative sentiments about the former President when given the opportunity. Our results demonstrate that certain segments of society are ‘motivated believers’ who are predisposed to accept misinformation that supports their political views. To our surprise, we also discovered that knowledgeable citizens were just as likely to associate Obama with Islam as those who are less knowledgeable. Thus, although routinely condemned, smear campaigns appear to be quite effective at creating associations between targeted political figures and false rumors.