There were people who were not policy knowledgeable,   that voted for Obama partly because he was  black.  **I would point out that white culture used to use what, 1/8 black, was enough to make a person 'black'? Whites wanted their race 'pure' at the time.  Pres. Obama had  no choice in the label.   

I read his books, it was more about his interest in his paternal side, his black father, because he didn't have a chance to know that side of family history.     His mixed influences in his life certainly shaped his tolerance, and his acceptance by a wide range of people.   I can think of worse reasons for voters to like Obama the person.     He had a difficult period to work with, but I"m much happier at the end of his second term than I was at the end of Pres. Bush's second term.   

I'm sure his racial mix brought the conversation of racial bias into our culture again.   It didn't create the bigotry, it just exposed that it hadn't disappeared.