The long reach of US party politics: Transnational campaign involvement among democratic partisans living abroad

Much is known about the factors that shape partisan campaign activism in the United States and other democracies. In contrast to this voluminous literature, political scientists have given relatively little attention to an emerging phenomenon in contemporary party politics: the mobilization via “emigrant party branches” of partisans living outside of the territorial borders of their native country. We address this gap in the literature through an analysis of Democrats Abroad—the official overseas arm of the US Democratic Party—during the 2024 election cycle. Drawing from an original two-wave panel survey of party members, we demonstrate that some of the forces that prompt campaign activism in the domestic United States hold for partisans overseas. At the same time, factors pertaining to the migration experience and settlement in another country also affect engagement in American campaigns. Most notably, we find that overseas Democrats who become integrated into the party system of their residential country are more likely to participate in American elections from the distance. This finding contributes a fresh perspective to models of political transnationalism and “campaign spillover” in electoral research—that is, the impact that partisan engagement in one context has on subsequent involvement in separate domains.