Supplementary materials to: Testing cognitive and interpersonal asymmetry vs. symmetry among voters in the 2020 presidential primaries

During the 2020 U.S. Presidential primary season, we measured candidate support and cognitive and interpersonal variables associated with political ideology among 831 U.S. participants. Cognitive style variables included openness to experience, active open-minded thinking, dogmatism, and preference for one right answer. Interpersonal variables were compassion and empathy. We modeled candidate support across the political spectrum, ranging from the most conservative to the most liberal (Trump, Bloomberg, Biden, Warren, Sanders), testing competing pre-registered predictions informed by the symmetry and asymmetry perspectives on political ideology. Specifically, we tested whether mean levels on the variables of interest across candidate supporters conformed to patterns consistent with symmetry (i.e., a curvilinear pattern with supporters of relatively extreme candidates being similar to each other relative to supporters of moderate candidates) vs. asymmetry (e.g., linear differences across supporters of liberal vs. conservative candidates). Results broadly supported the asymmetry perspective: Supporters of liberal candidates were generally lower on cognitive rigidity and higher on interpersonal warmth than supporters of conservative candidates. Results and implications are discussed.