Rallied by thy neighbor: how minority spatial concentration increases voter turnout

Spatial concentration is believed to increase political engagement among minority groups by fostering intra-group contact and strengthening political group consciousness. This study empirically evaluates this relationship with a focus on lesbians, gays, and bisexuals (LGB), extending the scope of the existing literature beyond ethnoracial groups. Using Swedish population-wide register data, we identify over 20,000 LGB individuals and nearly 8 million of their comparable heterosexual peers and track their validated turnout across four elections (1994-2022). To estimate the causal effect of neighborhood LGB concentration on voter turnout, we apply a triple-difference approach, leveraging fine-grained geolocation data. The results are clear: LGB individuals are significantly more likely to vote when surrounded by more LGB neighbors. The paper provides rare causal evidence that spatial concentration can mobilize electoral participation, thereby advancing our understanding of political geography, urban politics, and minority electoral behavior.