So don’t.
Forget about “understanding” or “reaching out” to Trump voters. Their concerns are largely delusional, their “solutions” are diabolical and their preferences are vile.
But they’re only 20% of the country.
The people you need to reach are the non-voters. They aren’t staying home because they’re vicious shits who hate foreigners, they’re staying home because the American electoral and political systems are grotesquely corrupt.
Q: why was Citizens United bad?
A: because the unrestricted flow of money into politics is blatantly and severely corrupting.
The effects of Citizens United aren’t a thing that is going to happen. They’re a thing that has happened. And, as predicted, it utterly corrupted both parties.
That’s what needs fixing. You will always have a minority of citizens who are bigoted shits; every country does. The key is to build the system so that they don’t take control.