Different theoretical approaches trying to analyze the behavior of citizens in political participation and election in a democratic system. Among these explanations highlights the rational choice theory applied to the political context, which assumes that the voter can identify, in an atmosphere of complete information, which is the party that is less distance from their preferences and demands collectives (public policy). In this sense, is modelled as in a market interaction between two actors on the one hand, voters who act rationally, demanding the provision of public goods, through the votes, and on the other hand, politicians who offer the first a given amount of these assets through its proposed government.