Don't bet on it. My entire family is black, and they all vote liberal Democrat. Not a single one of them is going to vote for Cain because he looks like them. On the contrary, they're going to view him as a 'traitor' to his race - a 'sell-out' to the 'racist, bigoted Republicans'.
Sorry, but that is true level of their indoctrination, and it's as solid as a rock.
You are correct, the indoctrinated liberal blacks will not. But there are also a significant number of not so liberal blacks, and for them the stigma/shame/whatever will not be present if they want to pull the lever for Cain.
I never said it will be 50:50. But it could easily be 80:20 and that is a huge loss for democrats.
I believe that is the case with your family and many others, but I have to say I’m seeing some real changes where I live (Atlanta area). I am beginning to think there was something to that one poll that showed 24% of blacks voting for Cain.