This article uses new survey evidence from Tunisia, conducted shortly after the three first elections following the Arab Spring, to explain dynamics in electoral behaviour. We find that the strongest and most consistent predictors of vote choice were gender, religiosity and attitudes to the role of Islam in public life. Economic attitudes, other socio-demographics and clientelistic motivations were consistently less or not important factors. These findings support the notion of a paramount Islamist-Secular divide, which is distinct from the Western Left-Right divide, in the Arab World. We also find evidence that Tunisian voters underwent a learning process over the course of elections. Overall, we present evidence to suggest that the primacy of the Islamist-secular axis of political conflict is, in accordance with the evidence from other early divides in transitional democracies, elite-driven, and so is likely to decline in importance over time.