Simple, some GOPers fantasize that a conservative black woman would be a brilliant choice of nominee, because she's black and female and therefore PC enough to beat Shrillary. What they fail to see, as your questions point out, is that a) we have no idea what her politics are and b)a black woman ain't getting elected president anytime soon.
If I had to choose (and hopefully we'll get a chance), I'd like to see this Senator Coburn or possibly John Cornyn make a good run...both are strong conservatives and have backbones!