How can we explain the number of parties that enter electoral competition? Related to this, how can we explain the coordination of voters around a subset of these parties? These questions are fundamental to representative democracy and their implications are far ranging. For example, where there are too many parties of a particular type, perhaps Left-of-Center, and voters fail to discern which oens are truly viable, one well-coordinated party on the Right may overwhelming sweep to power despite the relative low levels of popular support. Political scientists have long investigated these questions, typically through quantitative, cross-national institutional analyses, but debate still exists on imporatn topics such as the effects of differences in electoral laws on both entry and coordination. This project leverages a cotnrolled comparison to provide clear and straightforward insights into both classic and original causal arguments. In the U.K., elections to the regional parliaments take place within the smae geographic districts as elections to the national parliament. The electoral rules used in these two sets of elections, however, are different. This creates a controlled comparison where we can explore the counterfactual: how would entry and coordination vary if we modified the electoral rules, but left the set of voters and the districts' characteristics intact? This research will explore this question by integrating three sources of data to provide a nuanced picture of strategic party entry and voter coordination: (1) electoral data disaggregated to the district level; (2) qualitative evidence gathered from interviews with party leaders about entry decisions; and (3) individual-level survey data about vote choice.

Findings from this project should be applicable in a number of countries around the world that are facing debates on the merits of electoral reform and political devolution. Especially regarding mixed member systems, where the implications for strategic entry and coordination are still unclear, the finding of this project will speak directly to this important institutional choice. As mixed member systems are currently the most popular new form of electoral rules under adoption around the world, this project stands to make an important contribution to the decisions made by reformers.

Project Report

The reseacher's project was to learn about electoral competition between political parties in the United Kingdom, which is a considerably more diverse institutional environment than the United States. In the UK, political parties are elected to four separate levels of government under four different sets of electoral rules. This constitutes an interesting "natural experimental" opportunity to explore how the same parties make decisions under different institutional rules. The researcher traveled throughout Scotland, Wales, and England to interview several political party leaders in an effort to learn something about how these diverse institutional rules effect the decisions they make in contesting elections. The findings of the study indicate that changing the rules under which parties are elected to government has profound implications for the ways in which those parties wage their campaigns, select candidates for office, and allocate their time, energy, and financial resources. Whereas this would have been an impossible question to study in the US, the institutional variation across levels of government in the UK made the country a fitting case to explore different hypotheses about party behavior. The findings of the study contribute answers to specific questions in the academic field of electoral scholarship as well as contribute to our understanding of democratic representation more broadly. For electoral studies, the project links certain institutional rules (like SMD, mixed-member, STV, and proportional represetation) to certain types of behavior on the part of political parties. More generally speaking, the findings of the project demonstrate that designers of political constitutions and electoral rules can make these choices with an eye toward influencing the number, type, and relative sizes of political parties that eventually gain representation in democratically-elected legislatures.

National Science Foundation (NSF)
Division of Social and Economic Sciences (SES)
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Brian D. Humes
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Washington University
Saint Louis
United States
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