Indeed, they were trotted out as black every time they could be.
And they were never candidates for president. Never.
Powell was mentioned, consistently said his wife had vetoed the idea, never did say he considered it. But Bush pointed out Powell was black over and over.
Rice was, to my knowledge, never touted as a presidential candidate. She did not have the stature until Bush appointed her NSA, and since then she's lied so much she really couldn't run for dogcatcher. She had problems with getting Senate approval to be Secretary of State over the credibility issue. ("Whooda thunk?" - a real NSA, for one.)
And, again, Bush points out she is black every chance he can.
Arf