Yo, it's all about the sociology - I mean, there are a lot of great African-American singers here- and so the black vote gets split. Being less than 20 percent of the population, it's no wonder that the "fringe" blacks are getting eliminated. Yes, more than blacks are voting for Melinda and Lakisha and Jordin, but we're talking about how people lean when they vote, and certain people tend to vote for their own race (or group).
I think that tendencies are working to Sanjaya's benefit - he and Jordin split the youth vote, he gets the Indian (and maybe all the non-American) voters, and the girls who have a crush on long hair. Sorry, Simon, it is NOT a singing contest...