It's the African American voter who votes more on party than ideology. They've done polling on things like vouchers and Social Security partial privatization. They do well with black voters-- until you tell them that those are "Republican" ideas.
I have statistics that show that blacks are receptive to some Republican ideas, if you don't connect it to the party itself. I don't disagree with you, but if it's true that blacks vote on party moreso than ideology, why are most black congresspeople strongly liberal?