This article says research shows evaluation of evidence is skewed by partisanship - not a surprise. If my kid shoplifts a pack of gum, it's a youthful prank that needs a discrete consequence. If a kid from a family I don't like shoplifts that gum, well, you know it's a reflection of the parenting and that kid needs to be nailed hard or he'll end up a serial killer. Unfortunately, our politics have gotten to the same irrational state.
However, the article ended on a positive note:
"... there is some good news. Researchers are finding that there are ways around strong partisan affective polarization — and they don’t even depend upon the two sides coming to an agreement on actual policy. In a 2019 study involving nearly 1,000 political partisans, “warm contact” between political leaders did more to reduce affective polarization and negative opinions about the other party than issue compromise."
Quote from article by Maggie Koerth-Baker.
I consider this good news. Our political representatives have more in common with each other than not. They have to go through the rigors of our election process, spend time away from loved ones, and get blamed for all kinds of stuff they can't control. The moments they're nice to each other aren't making the news when covering conflict boosts ratings.
All we have to do is make every positive interaction between opposing parties go viral! That will nudge the news organizations into giving us more positives, and politicians will see they get more free publicity from being nice to the opposition, so they'll quit hiding friendships and openly hug their buddies across the aisle. It will be self-perpetuating cycle.
And we'll all get back to considering issues more rationally.
It has been done - let's see more of it!
(Update 7/22/2020: COVID's working against this, dang it.)