Not true. I had a very close relationship with a black family who lived in a cul de sac across from me when I moved into this house nearly 29 years ago.  The first neighbors to welcome us to the neighborhood.  We used to play poker together every month.  His name was Kirby, and he had been the production manager for Robinson Dairy before he started his own business, "Kirby's Frozen Yogurt."  A few years after we moved in, Kirby showed up a bit late for our poker game.  I said, "Hey, Kirby, I just saw the "for sale" sign in front of your house!  Every house in the neighborhood just went up 20% in market value 'cause the darkies are moving out!"  He thought that was hilarious.  He was moving to a neighborhood about a mile away where the houses were worth more than twice as much to get a better class of neighbors.

But in general, most successful blacks support the Democrats because they don't want to have to support their poor friends and relatives, either.  Same goes for Hispanics.