It's very straightforward. We've always known that, with painfully few exceptions, feelings of white supremacy are among the very most important qualifications for membership in the Republican Party. Racists are just naturally drawn to the GOP. It's been that way since the Nixon era and virtually anyone who has ever voted for a Republican since those days has done so as a perverse "socially acceptable" expression of their semi-cloaked racism.
Now that Trump has emboldened them, however, Republicans aren't even trying to hide their racism. When they saw him gliding down that gold escalator to announce his candidacy, they saw a measure of deliverance. These "very fine people" saw a man who was more than just a symbol, they saw permission and freedom to be themselves and let their racist freak flag fly. Case in point, last weekend's Trump "Save America" rally when Rep. Mary Miller of the 15th district of Illinois said the magic words that the crowd came to hear.
As you see above, Rep. Miller adheres to the republican hope that the way out of white folks becoming the minority that they are rapidly becoming is to have more, many more, white babies and she is grateful for "President" Trump, Moscow Mitch and the Federalist Society for providing 3 new black robbed Talabanista "justices" who helped finally overturn Roe v. Wade. When she made her "victory for white life" comment the GOP crowd cheered. They loved her in a "She thinks just like me!" sort of way. Hell, Tucker Carlson and Sean Hannity probably had to be treated for Priapism as soon as they heard her speak those magic words.
A few days later on Tuesday, Republican voters in the newly re-jiggered Illinois-15 chose Mary Miller to represent them in Washington, Well, of course they did! It's who they are!