ABSTRACT
This chapter argues that the best way to understand the political organizations is to think of them as mechanisms. It also argues that the substitutability of parties, interest groups, and direct action groups is only true from the perspective of activists in under-represented groups looking to form niche organizations. The chapter explains that political participation in general is motivated by both expressive and instrumental concerns, and that participation in niche organizations is no exception. The typology covers each organization in the movement, classifying them according to the method by which their members try to influence the chain of democratic delegation: pressuring politicians, circumventing politicians, or replacing politicians. Mainstream political organizations need the oligarchic features, because they have to handle multiple high-salience issues and must stay on-message in each of their carefully calibrated campaigns. The organizational structure of mainstream parties prevents niche groups from changing them from within.
