This research studies the role of Chile, Colombia and Peru, South American countries of the Pacific Alliance (PA) regional integration mechanism, in the Union of South American Nations (UNASUR) and in the PA itself, in the period 2008-2018. This, within the framework of Gramscian notions or derived from his philosophy, hegemony and consensus, applied in such regional integration processes. Thus, we will evaluate if these countries were able to challenge consensual leadership in South America. To do this, we will analyze, through relevant theories, concepts and data, the role of these States and other actors in the sense of the Gramscian expanded State.