There is a phrase in the history of party sociology that was put forward about sixty years ago and is still valid today: "Modern parties are much less determined by their program or by the class origin of their supporters, as compared to the nature of their organization" (Duverger, 1976: 20).
This sophisticated and pioneering observation by Maurice Duverger was made at a time when the prevailing view stated that political parties are primarily determined by their electoral base and their political program, rather than by their organization. However, already back then, their organizational crystallization and internal function tended to over-determine their political character and dominate over their electoral or programmatic imprints. The most tangible example of this trend was found in the (third-worldist) communist parties, whose program and structure of their electoral base were over-determined by the (qualitative) characteristics of their bureaucratic organization.