Perry Bacon Jr summarized this study over at 538.

https://fivethirtyeight.com/features/democrats-are-wrong-about-republicans-republicans-are-wrong-about-democrats/

Overcoming impressions on the Republican side is difficult because the overwhelming majority of Republicans support Trump. Nationwide studies done in June suggested almost 50% of Republicans support separating children from their parents at the border. 

Bacon noted the following:

You might say, “This is just one study.” And it is. I suspect that some of these results just show Americans’ innumeracy — most blacks are Democratic-leaning, but most Democratic voters are not black. But I wanted to highlight this research in part because I think it speaks to the political moment we are in, and the study’s findings fit well with other recent research on political polarization. Lilliana Mason, a political scientist at the University of Maryland, published a book earlier this year that I highly recommend called “Uncivil Agreement: How Politics Became Our Identity.” In describing American politics today, she argues that partisan identity (Democrat or Republican) has become a “mega-identity” because it increasingly combines a number of different identities.

Mason writes in her book [emphasis hers]:

“A single vote can now indicate a person’s partisan preference as well as his or her religion, race, ethnicity, gender, neighborhood and favorite grocery store. This is no longer a single social identity. Partisanship can now be thought of as a mega-identity, with all of the psychological and behavioral magnifications that implies.”

In other words, if you told someone on the phone whom you had never met before that you are white, that single fact would not tell them much more about you. But if you told them that you are a Republican, they could reasonably assume that you are not black, lesbian, gay, transgender or bisexual, nonreligious or Jewish. They could also assume that you don’t live in Washington, D.C., and that you don’t believe racial discrimination is the primary reason blacks aren’t making more advances in today’s America. If you told them you are a Democrat, they would have good reason to believe that you are not a white evangelical Christian and don’t live in coal country in Kentucky. (We should not exaggerate how perfectly sorted people are: In raw numbers, there are still plenty people who buck their party’s stereotypes — young and non-evangelical Republicans and Democrats who are religious and non-urban.)