Published online by Cambridge University Press: 02 June 2016
Which parties benefit from open-list (as opposed to closed-list) proportional representation elections? This article shows that a move from closed-list to open-list competition is likely to be more favorable to parties with more internal disagreement on salient issues; this is because voters who might have voted for a unified party under closed lists may be drawn to specific candidates within internally divided parties under open lists. The study provides experimental evidence of this phenomenon in a hypothetical European Parliament election in the UK, in which using an open-list ballot would shift support from UKIP (the Eurosceptic party) to Eurosceptic candidates of the Conservative Party. The findings suggest that open-list ballots could restrict support for parties that primarily mobilize on a single issue.
Department of Government, London School of Economics (email: j.blumenau@lse.ac.uk); Department of Politics and International Relations, University of Oxford and Nuffeld College (email: andrew.eggers@nuffeld.ox.ac.uk); Department of Methodology, London School of Economics and Department of Political Science, University of Zurich (email: d.hangartner@lse.ac.uk); Department of Government, London School of Economics (email: s.hix@lse.ac.uk). We acknowledge financial support from the Electoral Reform Society and the London School of Economics (LSE) for supporting the research for this article. We thank seminar participants at the LSE, Stanford University, the University of Sheffield, the University of Essex, the University of Leuven and three anonymous reviewers for helpful comments. Previous versions of this article were presented at the 2014 annual meetings of the American Political Science Association and the European Political Science Association. Data replication sets are available from https://dataverse.harvard.edu/dataverse/BJPolS and online appendices from http://dx.doi.org/doi:10.1017/S0007123415000629.