As someone who has lived...

...most of his life in "cultural isolation," as Ross Douthat put it in a recent piece, "The Idea of Trump’s Electability," I totally understand how a typical white suburban Republican could think Donald Trump's "popularity" with blacks and Hispanics wouldn't be a whole lot worse than Mitt Romney's. Douthat writes (my emphasis):

Trump's favorability/unfavorability ratings with Hispanics are 12/77. If you go back to last August, before the campaign began, Trump had a 20 percent favorable rating with African-Americans; by Republican standards that’s not terrible. Six months of race-baiting later, he’s winning 5 percent of the black vote against Hillary Clinton. And women … well, he’s losing women, let’s put it that way, on a scale that no Republican nominee ever has before.

Hence his essential unelectability, which no centrist positioning is likely to much change. And the fact that so many Republican voters can’t seem to see this, haven’t been able to see this, may be a sign of cultural isolation above all. They can see how Trump might be able to win on the issues if he hadn’t alienated so many millions of Americans on the basis of their race or sex … but they can’t quite grasp how powerful that alienation is for the people who experience it, and how impossible it will be for Trump to overcome.

Now, admittedly, it's no scientific sampling, but the blacks and Hispanics I've talked to about Trump don't seem to react in the same way as I would imagine they did with Romney. I'll bet it was more indifference than anything else in regard to the Mormon plutocrat. But with Trump it's more like hatred -- visceral hatred. And, if I'm right (and sometimes I am), blacks and Hispanics will turn out in huge numbers this November to vote against the Donald. It's that level of hatred, I think, that the polls can't measure.

As for women, well, the Times has another story this morning which mentions:

Katie Packer, who runs an anti-Trump group and co-founded a consulting firm that helps Republicans communicate to women.

Now, I get that many Republicans rarely come into contact with blacks or Hispanics, but don't these guys have mothers, sisters, daughters and/or wives? Are women really such an exotic interest group that Republicans need a consultant to help them "communicate to" them?