The ability of the news media to mobilize voters during an election campaign is not well understood. Most extant research has been conducted in single-country studies and has paid little or no attention to the contextual level and the conditions under which such effects are more or less likely to occur. This study tests the mobilizing effect of conflict news framing in the context of the 2009 European Parliamentary elections. The unique multi-method and comparative cross-national study design combines a media content analysis (N548,982) with data from a two-wave panel survey conducted in twenty-one countries (N532,411). Consistent with expectations, conflict framing in campaign news mobilized voters to vote. Since the effect of conflict news was moderated by evaluations of the EU polity in the general information environment, conflict framing more effectively mobilized voters in countries where the EU was evaluated more positively.