I think he has slightly more contempt for African-Americans than whites...
Too many people have relayed his racist comments of the past... then there is the 'shithole-countries' remark and countless others that he made 'in private'...
That said, he is intentionally courting the neo-nazis and racists as much as he possibly can- he knows that they will be his most militant followers... so he tosses them red meat and keeps them in a frenzy so they will be primed to do his bidding when the time comes...
And that time is rapidly approaching...