Federal elections between 2008 and 2019 saw a great of volatility in Quebec, with important consequences for election outcomes. The surge in New Democratic Party (NDP) support in Quebec led the party to official opposition, while Liberal gains in 2011 led the party to a majority government, and Bloc Québécois gains in 2019 helped to reduce the Liberals to a minority. To what extent was this volatility driven by voters switching parties and to what degree was it driven by voters entering and exiting the electorate? This article uses ecological inference based on riding-level data to examine the dynamics of party competition in Quebec from 2008 to 2019. We show that while voter mobilization mattered to volatility, vote switching was the important driver of changing party fortunes during this period.
