In the absence of a convincing transformationalist theory of democracy, evaluations of the EU’s democratic performance as a non-state, but transnational polity are problematic. This observation is highlighted further by the introduction of the European Citizens’ Initiative (ECI) in the Lisbon Treaty, which – despite its idiosyncracies – has been characterized as the world’s first transnational citizens’ initiative. In terms of participatory democratic theory, it is considerably more than a mere petition, but also less powerful than a full-fledged citizens’ initiative. From a deliberative perspective, on the other hand, the ECI’s main potential lies in its ability to foster transnational contestation and deliberation, as demonstrated by cases such as e.g. the Right2Water and Stop TTIP initiatives. Such initiatives do however illustrate the problems that traditional state-centered theories of publics, publicness and the public sphere have in dealing with processes that by their very nature transcend, but by no means replace existing spatial, cultural and linguistic boundaries across the EU. The ECI’s organizational requirements strongly suggest that the success of an initiative requires the interplay of publics as well as processes of mobilization and contestation at the local, regional, national and transnational levels. The proposed paper reflects on this both as a challenge and as an opportunity for (a) the continued democratization of the EU and (b) the further development of a theory of transnational democracy, in particular with a view to conceptualizing the role and very definition of the publics, publicness and indeed the public sphere within transnational democracy. Particular emphasis within this analysis is placed on the role of digital media as a facilitator in the development of publics that are by definition neither exclusively subnational, national or transnational, but transcend and elude such categorizations. Empirical illustrations are drawn from the formal Right2Water and the informal Stop TTIP campaigns.