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Third-Party Strategy under Plurality Rule: The British Liberal Democrats and the New Zealand Social Credit Party

Quinn, Thomas (2017) 'Third-Party Strategy under Plurality Rule: The British Liberal Democrats and the New Zealand Social Credit Party.' Political Studies, 65 (3). 740 - 763. ISSN 0032-3217

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This paper examines the strategic options facing small centrist third parties in two-party parliamentary systems operating under the single-member district plurality (SMDP) electoral system. It uses a spatial model to show that centrist third parties are better off targeting the 'safe' districts of a major party rather than marginal districts. Furthermore, it is optimal to target one party's districts, not both, to benefit from tactical and protest voting. The paper also questions the implicit conclusion of the median-legislator theorem that pivotality-seeking is the best strategy for a third party, at least under SMDP, because that would usurp voters' ability to select the executive directly, a key feature of two-partism. Finally, the paper shows that third parties can damage themselves if they 'flip' from opposition to one major party to support for it. Evidence is provided for the British Liberal Democrats and New Zealand?s historic Social Credit Party.

Item Type: Article
Uncontrolled Keywords: Duverger’s law, plurality electoral system, third parties, Liberal Democrats, Social Credit Party (New Zealand)
Subjects: J Political Science > JA Political science (General)
J Political Science > JF Political institutions (General)
J Political Science > JN Political institutions (Europe) > JN101 Great Britain
Divisions: Faculty of Social Sciences > Government, Department of
Depositing User: Jim Jamieson
Date Deposited: 29 Sep 2016 10:46
Last Modified: 21 Jan 2020 19:15

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