The determinants and consequences of ideological ambiguity: strategies, electoral impact, and coalition formation

The responsible party model assumes that parties should present clear and coherent policy preferences to voters, enabling accountability and informed choices. However, parties often deviate by adopting ambiguous or vague positions. This dissertation, structured as a collection of papers, investigates the determinants and consequences of ideological ambiguity in European democracies. The first paper explores why parties adopt ambiguous positions. While existing literature emphasizes ambiguity as a strategic tool to attract diverse voters, it often overlooks intra-party dynamics. Using data from the Chapel Hill Expert Survey (CHES), Comparative Candidate Survey (CCS), and European Social Survey (ESS), the study shows that ambiguity stems not only from divergent voter preferences but also from ideological heterogeneity within parties. The second paper examines the electoral impact of ideological ambiguity. Although ambiguity may broaden a party’s appeal, it carries risks. Analyzing data from the European Election Study (EES), Euromanifesto study, and CHES, the paper finds that ambiguity is generally an ineffective electoral strategy. However, when combined with valence appeals, such as competence and honesty, ambiguity can attract ideologically distant voters while reinforcing support among the party’s base.The final paper investigates the role of ambiguity in government formation. Traditional policy-seeking theories assume parties have complete information during coalition negotiations, but ambiguity challenges this. Using data from the Representative Democracy Data Archive (REPDEM) and CHES, the study reveals that ambiguity heightens uncertainty about parties’ preferences and negatively affects government formation, especially in ideologically similar coalitions. Together, these papers deepen the understanding of why ideological ambiguity arises and its broader implications for electoral competition and government formation in European democracies.