A coalition of leftist political groups, civic movements, and grassroots organizations led by social activist Ada Colau won the Barcelona municipal elections of 2015 and is now governing the Catalan capital. The key to this success may well have been its critical positioning in relation to its tourism. Until recently considered a best practice in urban regeneration and a successful global destination, Barcelona has seen in the last 2 years a radical change in the public perception on tourism: from “manna from heaven” to serious issues that are affecting the quality of life of its citizens. This article looks into the factors that may have determined this political change, from the growth of tourism beyond what could be considered a critical threshold for an urban system, to the development of a critical discourse on tourism by the new coalition—attributed to its peculiar constituency and working methods—and the role of the media in airing this discursive shift. The article follows the thread of the “growth machine” theorizations and questions whether the increasing dimension of tourism in urban societies could be a driver for regime changes.