We're voting for a president, not a priest.
I doubt that Obama would be reaching out so explicitly to Christians if he didn't have to counter the right-wing noise machine that conned some people into believing that he's a Muslim. For one example, check out this exchange (h/t: Andrew Sullivan):
Woman: "I don't know about that Obama guy."
Me: "I'm an Obama supporter, do you mind if I ask what you're unsure about."
Woman: "He's a muslim and there is a biblical prophecy that a muslim will take over our country and destroy the world."
Me: "You're aware he is not a Muslim."
Woman: "He can say anything he wants."
Remember: these people vote.