We present, test, and extend a theoretical framework that connects disgust, a powerful basic human emotion, to political attitudes through psychological mechanisms designed to protect humans from disease. These mechanisms work outside of conscious awareness, and in modern environments, they can motivate individuals to avoid intergroup contact by opposing immigration. We report a meta-analysis of previous tests in the psychological sciences and conduct, for the first time, a series of tests in nationally representative samples collected in the United States and Denmark that integrate the role of disgust and the behavioral immune system into established models of emotional processing and political attitude formation. In doing so, we offer an explanation for why peaceful integration and interaction between ethnic majority and minorities is so hard to achieve.

Do presidential campaign advertisements mobilize, inform, or persuade citizens? To answer this question we exploit a natural experiment, the accidental treatment of some individuals living in nonbattleground states during the 2000 presidential election to either high levels or one-sided barrages of campaign advertisements simply because they resided in a media market adjoining a competitive state. We isolate the effects of advertising by matching records of locally broadcast presidential advertising with the opinions of National Annenberg Election Survey respondents living in these uncontested states. This approach remedies the observed correlation between advertising and both other campaign activities and previous election outcomes. In contrast to previous research, we find little evidence that citizens are mobilized by or learn from presidential advertisements, but strong evidence that they are persuaded by them. We also consider the causal mechanisms that facilitate persuasion and investigate whether some individuals are more susceptible to persuasion than others. , and the reviewers, as well as seminar participants at Columbia, Dartmouth, NYU, UCLA, and Yale, for assistance and helpful comments. Appendices, a replication archive, and additional analyses discussed in the text are available at http://research.yale.edu/huber.

Many political observers view get-out-the-vote (GOTV) mobilization drives as a way to increase turnout among chronic nonvoters. However, such a strategy assumes that GOTV efforts are effective at increasing turnout in this population, and the extant research offers contradictory evidence regarding the empirical validity of this assumption. We propose a model where only those citizens whose propensity to vote is near the indifference threshold are mobilized to vote and the threshold is determined by the general interest in the election. Our three-parameter model reconciles prior inconsistent empirical results and argues that low-propensity voters can be effectively mobilized only in high-turnout elections. The model is tested on 11 randomized face-to-face voter mobilization field experiments in which we specifically analyze whether subjects' baseline propensity to vote conditions the effectiveness of door-to-door GOTV canvassing. The evidence is consistent with the model and suggests that face-to-face mobilization is better at stimulating turnout among low-propensity voters in prominent elections than it is in quiescent ones.