Latin America had long been the one region in the world without major ethnic parties, but in recent years a couple of inclusive ethnic parties have registered important electoral victories. A substantial literature maintains that ethnic parties win by mobilizing their base through exclusionary ethnic appeals, but this article argues that such appeals are unlikely to be successful in regions such as Latin America, where ethnic polarization is low and ethnic identification is fluid and multiple. In these areas, inclusive strategies are more likely to be successful. Indeed, some parties, which the author refers to as ethnopopulist parties, have won votes from diverse ethnic constituencies by moderating their discourse, forming cross-ethnic alliances, and formulating a broad populist appeal. This article focuses on the most successful ethnopopulist party to date, the Movimiento al Socialismo (MAS ) in Bolivia. It shows how the MAS used an inclusive ethnic appeal and classical populist strategies to fuse traditional populist constituencies—politically disenchanted urban mestizos with nationalist and statist views—to its rural, largely indigenous base. The article also examines the extent to which these arguments can account for the varying performance of other parties in the region.