Neither Trump nor Clinton was especially well-liked. Data from a Pew survey conducted before the 2016 national conventions found that both candidates received mediocre ratings from supporters of their own party—and record low ratings from members of the opposing party. On a “feeling thermometer” scale of zero to 100 degrees, Clinton received an average rating of 12 degrees from Republicans, while Trump received an average rating of 11 degrees from Democrats. In fact, 68 percent of Democrats rated Trump at zero, and 59 percent of Republicans rated Clinton at zero—an extraordinary reading with no modern precedent.
As a result, even though many voters had reservations about their own party’s nominee, very few ended up defecting in November. It was once common for voters to choose, say, a Republican for president and a Democrat for senator. No longer: Recent elections have been characterized by unprecedented party loyalty and straight-ticket voting, and negative partisanship is a major reason.
The concept of negative partisanship was first developed by political scientists studying countries with multi-party systems, such as Canada and Germany. But today, it applies even more clearly to the United States. Our research shows that Americans increasingly are voting against the opposing party more than they are voting for their own party.