ABSTRACT
While most research on party polarization previously focused on the ideological extremity of party positions, in recent years a new form of polarization has emerged in the American electorate. Ordinary Americans increasingly dislike and fear those from the other party. This phenomenon of animosity between the parties is known as affective polarization. I summarize the evidence bearing on the extent of affective polarization, trace its origins to the power of partisanship as a social identity, and explain the factors that have intensified partisan animus. In closing, I consider the implications of heightened partisan animus for the democratic process.
