Social ties play a prominent role in individuals’ political decision-making. They influence partisan defections, political participation, voting decisions, and political information acquisition. Much of the literature has focused on personal social networks or geographically close networks. Yet, one’s social network might also include acquaintances or other connections in more distant places that are maintained via online networks. In this study, we exploit Facebook’s Social Connectedness Index, which reflects social connections across the United States, and we investigate the role of social connectedness in political decision-making among individuals who are located across distant geographical regions. Our results suggest that social connectedness between counties has a homogenizing effect on voting for the same presidential candidate, either Democratic or Republican. On the other hand, social connectedness is likely to have a differentiating effect on voting for an independent or a third-party candidate. Moreover, this effect is moderated by the socio-economic characteristics of the counties, such as education, race, population density, household income, industry, and gender composition.