This article analyses the characteristics of current Argentine political elites thourgh a quantitative study of the social backgrounds and political careers of Argentine national senators within the period 2001-2011 based on a database made by the author. Data shows a pluralization of senators’ profiles in comparison with previous terms. At the same time, justicialists are more heterogeneous than radicals. This study shows that the institutional reforms introduced in the Senate in 2001 opened the high chamber to the same processes of transformation in the political elites that were taking part in other governmental institutions, producing a pluralisation of social backgrounds and political careers. The way in which those backgrounds and careers changed was determined by the varied electoral performances of each party along with their different recruitment patterns, in the frame of social diversification and specialization processes.