This article analyzes the coalition regime of the National Front in Colombia and its popular legitimation through the 1957 plebiscite. The objective is to reconstruct the process that led to institutional reform and the central characteristics of the plebiscite. The argument includes two statements. On one hand, the central actors in the process were élite parties that, despite their divisions and historical confrontations, came together to defend their positions of power against Gustavo Rojas Pinilla’s intention to remain in the presidency and overcome the widespread violence that affected the country. On the other hand, the plebiscite was conceived as a means of social legitimation of the decisions of the élites and the mobilization in its support was highly successful, although its content imposed severe limitations on the democratic regime. It is an analysis of a historical conjuncture based on documentary analysis and electoral statistics whose sources are newspaper archives, official statistics and complementary bibliography