Does ostracism affect party support? Comparative lessons and experimental evidence

The success of anti-immigration parties (AIPs) in many European democracies poses a strategic problem for established actors: Immediate policy impact of AIPs can be averted by ostracizing them (i.e. refusing any cooperation), but this strategy may sway public opinion further in their favour. A comparative review shows large variation in the electoral trajectories of ostracized parties. We therefore propose a model of the context conditions that shape the repercussions of ostracism in public opinion. Under conditions that suggest substantial policy impact of an AIP were it to join a coalition government, ostracism should decrease the party’s electoral support. Vice versa, if context suggests strong “signaling” potential of an AIP if in opposition, ostracism should increase its support. To avoid apparent endogeneity of political context and party competition, the model is tested with a survey-embedded experiment on a representative sample from the Netherlands. Results confirm that ostracism is a double-edged strategy.