This chapter presents new evidence showing how drug cartels and their associates attacked municipal party candidates and mayors to take control over local elections, penetrated municipal governments, and subdued local economies, populations, and territories. Extensive interviews with former local officials, local economic actors, and local human rights activists show the development of subnational criminal governance regimes in Michoacán and Guerrero – two states ruled by leftist governors, where subnational authorities were purposefully unprotected by the conservative federal government. Cartels inflitrated local campaigns and municipal governments, established themselves as monopolists of violence and criminal taxation, and regulated economic activities in key economic areas. But they failed to do this in Baja California, where the federal government protected the president’s subnational co-partisan rulers. We discuss why, in a context of competition for turf, and state-cartel and inter-cartel conflict, drug lords and their associates developed highly coercive and predatory governance regimes, subverting local democracy, and opening a new era of intense civilian victimization.