Pre-electoral coaltion politics

DFG Project

In the research project with Thomas Gschwend, Oke Bahnsen und Anna Adendorf, we study how colaition politics influences voters and parties.


Research question/goal: In multi-party systems, parties often announce their coalition preferences during the electoral campaign. Our project focused on two aspects. The first was to understand how pre-electoral coalition signals influence voting behaviour. The second was to investigate under which conditions parties are willing to send coalition signals during election campaigns.

To explore how coalition signals shape voting behaviour, we conducted four different survey experiments during the 2018 Swedish general election, the 2020 Irish general election, the 2020 New Zealand general election, and the 2021 German federal election. To test when parties signal their preferred coalitions, we set up a comprehensive cross-country database of electoral coalitions in 398 legislative elections in 22 advanced industrialized democratic countries from 1946 to 2014. Furthermore, we collected pre-electoral coalition signals from newspaper articles in 17 elections in five countries. Using this extensive data set, we worked together with computer scientists from the University of Mannheim to train a classifier that automatically detects coalition signals from newspaper articles.

Our results provide central insights into the influence of coalition signals on voting decisions. First, coalition signals affect voting decisions by changing voters’ expectations about which coalitions are likely to form after the election. Second, voters are risk-averse with respect to coalition-directed voting. Third, breaking coalition promises reduces the propensity of voters to vote for the inconsistent parties. Fourth, motivation, information, and capabilities are preconditions for strategic voting. With respect to parties’ pre-electoral coalition strategies, parties prefer to form pre-electoral coalitions with partners who are on the same side of the ideological spectrum.


  1. Weighting parties and coalitions: how coalition signals influence voting behavior
    Thomas GschwendMichael F Meffert, and Lukas F Stoetzer
    The Journal of Politics 2017
  2. Coalition-directed Voting as a Lottery
    Oke BahnsenLukas F Stoetzer, and Thomas Gschwend
    Workshop on Coalition Politics Humboldt University 2022 2022
  3. How do coalition signals shape voting behavior? Revealing the mediating role of coalition expectations
    Oke BahnsenThomas Gschwend, and Lukas F Stoetzer
    Electoral Studies 2020
  4. Leihstimmen im Bundestagswahljahr 2013
    Lukas StoetzerSteffen ZittlauThomas Gschwend, and Tobias Witt
    Politische Psychologie 2015
  5. Estimating coalition majorities during political campaigns based on pre-election polls
    Lukas F Stoetzer, and Matthias Orlowski
    Journal of Elections, Public Opinion and Parties 2020
  6. Pre-electoral Coalition Strategies in Multiparty Systems
    Thomas GschwendLukas F Stoetzer, and Indridi Indridason
    European Political Science AssociationConference 2018 and Swiss Political Science Association (SPSA) Annual Conference in Zurich 2019 and 2021. 2021
  7. Come hither or go away? Recognising pre-electoral coalition signals in the news
    In Proceedings of the 2021 Conference on Empirical Methods in Natural Language Processing 2021