Across five experiments (four pre-registered, N = 4,431), we investigate whether emphasizing similarities between Republicans and Democrats can improve intergroup relations between the two groups. Members of both groups who were presented with evidence emphasizing similarities rather than differences in the psychological attitudes of both parties reported greater inclusion of the political opposition in the self, greater belief that common ground can be reached for major social issues, and warmer feelings toward the opposition. Inclusion of the political outgroup in the self mediated the effect of the similarities condition on additional outcomes, relating to more positive and less threatening perceptions of political opposition members. These findings held even when compared with a baseline condition with no information presented to participants. We conclude that by emphasizing the study of group similarities and by disseminating research in a way that highlights similarities, researchers could reduce intergroup hostilities in the political domain.
Keywords: differences; ideology; morality; politics; similarities.