Many Latinos already vote Republican, and the party’s already quietly dropped racism as a platform, if you haven’t noticed. The Democrats do nothing for most black people, partly because they’ve been a guaranteed voting base, and why do anything for someone whose votes you don’t want to win? The current Democratic President is a goddamned segregationist; at least Republicans know better than to run someone like that. The Vice President made her career by locking up mostly minorities.
I used to live in Memphis, where a similar history already played out. Up until the 50s or 60s, the Democrats were the party of racism against minorities, which, incidentally, should tell you something about how quickly the parties can change on this kind of issue. But in Memphis during the 20s through the 40s, most of the black vote went to Democrats, because the Democratic boss of the city, E.H. Crump, extended patronage to black community leaders, who in turn told their supporters to vote Democrat. Eventually some more politically oriented blacks began to realize Crump wasn’t doing anything for them, just bribing influential people for their support, and tried to make an alliance with the Republicans to break Crump’s power. The leading figure in this, Robert Church Jr., was driven from the city; his family mansion was seized by the city (which was informally controlled by Crump) and burned as a firefighting drill in retaliation. But for a brief period, the black vote became Republican again as Crump’s power waned, until the national party adopted the southern strategy, and it flipped back to Democrat.