If Obama were a white Democratic candidate, he'd be John Edwards. In other words, he's too much of a lightweight to have been nominated, if not for his melanin levels. He'd have been eliminated in the primaries.
I saw some Obama TV commercials early on that showed is white grandparents. I don't think that the Obama campaign wants to highlight his "white" side. He is after all 1/2 white and being raised in Indonesia and Hawaii I can't believe that he had problems because of the color of his skin. In fact most Hawaiians I know are darker than Barry!