Library Header Image
LSE Theses Online London School of Economics web site

Coalition formation in presidential regimes: evidence from Latin America

Bunker, Kenneth (2015) Coalition formation in presidential regimes: evidence from Latin America. PhD thesis, London School of Economics and Political Science.

Text - Submitted Version
Download (775kB) | Preview


This thesis explains coalition formation in presidential regimes with evidence from Latin America. The conventional view has been that coalition formation is considerably difficult in presidentialism, and as a result, parties have only exceptionally been expected to form coalitions. However, since the 1990s, the frequency of coalition formation has increased across the region. Most democracies have at some point elected a presidential candidate backed by an electoral coalition, or have been ruled by a president backed by a government coalition. This thesis presents three major findings that contribute to the development of a theory of coalition formation in presidential regimes. First, it shows that simple majority plurality for presidential elections, unicameralism, proportional representation, larger legislatures, smaller average district magnitudes, a higher effective number of electoral parties, and the government party’s legislative majority are crucial predictors of electoral coalition formation. It also shows that when an outsider presidential candidate is present, the likelihood of electoral coalition formation decreases. Second, this thesis shows that weak presidents elected with a low vote share are more likely to form government coalitions. It shows that simple majority plurality for presidential elections, longer presidential terms, unicameralism, smaller legislatures, and fewer legislative parties are crucial predictors of government coalition formation. It also shows that when the incumbent president was backed by an electoral coalition in the immediately previous election, or when the government is going through political turmoil, the probability of forming a government coalition increases. Third, it shows that coalitions may or may not form even when variables related to presidential power, electoral institutions, electoral systems, and party systems are not perfectly aligned. It shows that while presidential power is relevant, electoral arrangements and the party system are what ultimately determine coalition formation. While the former variable is a sufficient condition, the latter variables are both sufficient and necessary conditions. Finally, this thesis shows that political culture and critical junctures play an important role in exacerbating or ameliorating these structural incentives.

Item Type: Thesis (PhD)
Additional Information: © 2015 Kenneth Bunker
Library of Congress subject classification: J Political Science > JL Political institutions (America except United States)
Sets: Departments > Government
Supervisor: Panizza, Francisco and Hix, Simon

Actions (login required)

Record administration - authorised staff only Record administration - authorised staff only


Downloads per month over past year

View more statistics