Is There an Ideological Asymmetry in the Incumbency Effect? Evidence From U.S. Congressional Elections

The electoral advantage that incumbent legislators enjoy over challengers in the U.S. Congress has been investigated extensively in political science. Very few studies, however, have considered the role of individual differences when it comes to incumbency preferences among voters. Based on theory and research in political psychology, we hypothesized that political conservatives would exhibit stronger preferences than liberals for incumbents over challengers from the same party. Extensive analyses based on more than 150,000 voters from seven election cycles in the United States from 2006 to 2018 support this hypothesis. A significant effect of conservatism on incumbency preferences was observed in the U.S. Senate and House of Representatives, and it was not attributable to Republican Party identification. This ideological asymmetry is consistent with system justification theory and prior research linking conservatism to risk aversion and status quo bias. Practical implications and directions for future research are discussed.