1. plant the meme so that some folks start thinking, "oh, this might cause too many problems, a black man for presdinet. better vote for the white guy."
2. reinforce the ideas of those who're already racist and push the fence sitters to join in the racism
3. force the obama campaign to speak to the issue, reinforcing 1 and 2
4. they'll take the risk that some folks will defiantly vote for him, b/c they're embarassed by the racism.