Replication Data for: Gateways to White Nationalism: Leaders’ Online Rhetoric and Follower Engagement

White nationalist extremism is an increasingly dangerous global security threat. Yet how white nationalist leaders deploy ideological rhetoric online to sustain and expand their support base remains poorly understood. We theorize that leaders retain a central role in this decentralized movement, using their online platforms to consolidate and grow support through appeals emphasizing distinct elements of white nationalist ideology. To test this theory, we analyze 16,627,018 Twitter and Gab posts (2016–2021) from 64 U.S. white nationalist leaders and 11,303 followers. Our results show that leaders are highly influential: when they highlight specific issues, followers soon post similar content. Moreover, gendered rhetoric serves as a particularly powerful mainstream gateway appeal—even more than partisanship—engaging peripheral followers and prompting followers to post more racialized content. These results reveal how white nationalist leaders shape and market extremist ideology online and build follower networks, with important implications for understanding and disrupting radicalization.