Of course those coming into the country who haven't contributed anything to the U.S., will vote for the lunatic group who will promise to give them everything free. My guess is that the majority of honest immigrants will see things much differently and therefore vote differently.
Consider the sea changes from 1992 (B. Clinton v GHW Bush) to 1996 (B. Clinton v Dole) and from 2004 (Bush v Kerry) to 2008 (Obama v McCain). Foreign born citizens are not entirely tribal. Whether the gap widens or shrinks will depend on the candidates who run.
From what I have read, whites are the only major race/ethnic group that supports the GOP consistently. The Dem's push for immigration is not altruism, its self-serving. Note they have no interest in white immigrants from South Africa or brown immigrants from Cuba who tend to support Republicans.
If they're voting as legal citizens, more power to them. Whether or not the trend continues depends on where they're coming from. I think everyone realizes many immigrants come here for the freebies. And democrats know those freebies lead to votes. It's been that way a long time.
The aim of globalization is to set minimum wages as a universal standard. People from “shit hole countries” expect less, deliver less snd this will usher in the universal living wage and produce “liberal leftist commie” voters who are “union bots”. People who are basically just worker drones obeying instructions that are passed down the chain of command.
I don't think "foreign born" necessarily is limited to Central and South America. Folks emigrating from all parts of Europe - save the former Soviet bloc - would find the Democrats of even five years ago to be downright conservative. And from personal experience, most Europeans think America is downright backwards in its thinking and should be far, far more progressive than we are even today.
So, regretfully, I think we are only an election or two away from a Democratic supermajority from here on out, unless Gen Z surprises us.