Moral Bias in Large Elections: Theory and Experimental Evidence, American Political Science Review
We provide support for the claim that large elections may exhibit a moral bias, i.e., controlling for the distribution of preferences within the electorate, alternatives understood by voters to be morally superior are more likely to win in large elections than in small ones. . Using laboratory experiments we show that ethical expressive voters (voters who receive a payoff from taking an action they believe to be ethical) will have a disproportionate impact on election outcomes for two reasons. First, the choice of how to vote in a large election confronts voters with an essentially hypothetical choice --- when ethical expressive types face hypothetical choice situations they are more likely to choose outcomes on the basis of ethical considerations than on the basis of narrow self-interest. Second, as pivot probabilities decline the set of people who participate will increasingly consist of ethical expressives.
Timothy Feddersen, Sean Gailmard, Alvaro Sandroni
Feddersen, Timothy, Sean Gailmard, and Alvaro Sandroni. 2009. Moral Bias in Large Elections: Theory and Experimental Evidence. American Political Science Review. 103(2): 175-192.