In the last 50 years roughly 90% of African American voters have voted for Democrats. As noted above, Democrats have largely taken their votes for granted and ignored their interests. Mostly Republicans have ignored them as unreachable.
On the other hand, in the election just concluded, Hispanics voted for both parties. A Washington Examiner article has the data:
At 34 percent, Republicans turned in one of their better recent performances with Hispanic voters. If all margins hold as currently reported, Republicans will represent eight of the 30 most heavily Hispanic congressional districts in America. Three of those are South Florida districts with significant Cuban populations.Cuban Americans are known to favor Republicans; it is interesting that 5 Hispanic congressional districts not dominated by Cuban immigrants appear to have elected Republicans. If over time Hispanics continue to vote for either party, both parties will attend to their interests.