In this article it is argued that vertical nationalization of the party system is affected by the way in which parties and candidates adopt strategies to remain in competition under a given set of rules, since electoral rules offer different incentives for them to coordinate (or not) their efforts among the different electoral levels. For this purpose, based on information from the elections for Council, Assembly and Chamber in Antioquia between 1997 and 2011, it was found that the changes in electoral rules in 2003 and their effect on the way in which politicians organize themselves for elections are a factor that affects vertical nationalization of the party system, distancing the competition on the municipal level from that which takes place on the regional and national levels.