<p>Many countries allow external citizens to vote from abroad. But while research has explored when external citizens can, and actually choose to, take up this transnational practice, little research investigates <i>who external citizens vote for</i>, centring almost exclusively how they differ from voters in the country of origin. We highlight two transnational drivers of external citizens’ vote choices. First, exclusion abroad should push them to engage in rejection-based transnationalism and thus increasingly support parties offering diaspora-inclusive homeland identity narratives in their country of origin. And second, transnational mobilization, specifically by state bureaucrats abroad and diaspora organizations, should shape external citizens’ votes. We test these arguments using data on all Turkish elections where external voting was possible. As theorized, we find that the ruling AKP receives more support among the diaspora in countries with more exclusionary citizenship policies and higher levels of transnational mobilization. This paper advances our understanding of transnational citizenship, external voting, transnationalism, and diaspora engagement.</p>