92pct were willing to sacrifice at least some money to help their inparty & hurt the ouparty; strong partisans & extreme ideologues sacrificed more resources for the inparty, wherereas the opposite occured for the outparty

Altruism and Spite in Politics: How the Mind Makes Welfare Tradeoffs About Political Parties. Alessandro Del Ponte, Andrew W. Delton & Peter DeScioli. Political Behavior, Jan 1 2021. https://link.springer.com/article/10.1007/s11109-020-09660-z

Abstract: How much will people sacrifice to support or oppose political parties? Extending previous work on the psychology of interpersonal cooperation, we propose that people’s minds compute a distinct cost–benefit ratio—a welfare tradeoff ratio—that regulates their choices to help or hurt political parties. In two experiments, participants decide whether to financially help and hurt the inparty and outparty. The results show that participants were extremely consistent (> 90%) while making dozens of decisions in a randomized order, providing evidence for tradeoff ratios toward parties. Moreover, participants’ ratios correlated in the expected directions with partisanship, political ideology, and feelings of enthusiasm and anger toward each party, corroborating that these ratios are politically meaningful. Generally, most participants were willing to sacrifice at least some money to help their inparty and hurt the outparty. At the same time, a sizable minority hurt their inparty and helped their outparty. Welfare tradeoff ratios push our understanding of partisanship beyond the classic debate about whether voters are rational or irrational. Underneath the turbulent surface of partisan passions hide precise calculations that proportion our altruism and spite toward parties.