This article evaluates the effects of violence related to the operations of drug-trafficking organizations (DTOs) on electoral competition, defined by the number of electoral alternatives or candidates in Mexico’s municipal elections. I find that the killing and threatening of politicians, which are effective tools to influence politics, jeopardizes competition in violent Mexican municipalities by reducing the number of candidates. This result is not only probabilistically robust but also meaningful. The number of candidates can fall to one in the more violent municipalities. However, DTOs can also provide (illegal) funding to politicians to facilitate their candidacies. I find that as confrontation intensifies among DTOs, the negative effect of violence on electoral competition moderates. This finding suggests that DTOs finance candidates to capture municipal governments when facing intense competition and attacks from other DTOs. In addition, DTOs in this context may also provide protection to their preferred candidates from other competing organizations. These factors temper the negative effect of violence on electoral competition.