Radical populist parties receive greater audience support on social media: a cross-platform analysis of digital campaigning for the 2024 European Parliament election

Social media platforms play an increasingly important role in political campaigning, enabling parties to bypass traditional media and mobilize support directly. While prior research highlights the online prominence of far-right and radical populist actors, most studies are limited to single platforms or national contexts. This study presents the first cross- platform and cross-national analysis of digital campaign communication by 401 parties across all 27 EU member states during the 2024 Euro- pean Parliament election. Using data from Facebook, Instagram, TikTok, X/Twitter, and YouTube, we examine party activity and audience engage- ment. By linking digital trace data with expert surveys, we test whether populist radical right parties disproportionately succeed in raising engage- ment online. Our findings confirm strong platform-specific advantages of radical populist parties, particularly on TikTok, YouTube and Facebook. We also observe high engagement for far-left populist parties with similar emotional and anti-elitist communication strategies. The more Eurosceptic positions a party holds, or the more frequently experts describe them to use emotional appeals or anti-elitist communication, the more audience engagement they received across several platforms. Overall the findings emphasize a disproportionate online support for radical populist parties across the European Union.