In recent years, pessimism about plebiscitary intra-party democracy has been challenged by assembly-based models of intra-party democracy. However, research has yet to explore the emergence of new power dynamics in parties originating from the implementation of deliberative practices in their intra-party democracy. We investigate how deliberative democratization reshuffles power relations within political parties through a case study of Agora, an internally deliberative movement party in Belgium. Employing a process-tracing approach using original interview and participant observation data, we argue that while plebiscitary intra-party democracy shifts power towards passive members prone to elite domination, our case suggests that deliberative intra-party democracy shifts power towards active members that are more likely to be critical of elites. ...