Klein describes neatly and concisely what has changed in our electoral politics, using political science research from scholars like Alan Abramowitz and Steven Webster of Emory. In the 1970s, voters tended to split tickets between, say, congressional and presidential races; in that decade the correlation of the two votes was 0.54. In the 1980s it rose to 0.65. Now it is 0.97! Just as stunning, another researcher, the political scientist Corwin Smidt, found that today’s self-proclaimed independents “vote more predictably for one party over another than yesteryear’s partisans.” The key here, however, is what Abramowitz and Webster call “negative partisanship” — that people are now more motivated by their antipathy for the other party than by affinity for their own. The willingness of ardent Trump supporters to stick with him through scandal, outrage and actions that may damage their own economic standing becomes more understandable — criticizing him or seeing him suffer a defeat means that the evil enemy has gained a victory.
— Read on www.nytimes.com/2020/01/28/books/review/why-were-polarized-ezra-klein.html