Generalist Interest Organizations and Interest System Density : A Test of the Competitive Exclusion Hypothesis

We examine the fate of generalist interest organizations as interest communities become more crowded. One of the core ideas of population ecology theory is the notion of competitive exclusion. This hypothesis suggests that through niche partitioning among similar organizations and the comparative advantages of specialist organizations, generalists typically found in heavily populated systems will find it more difficult to secure members than their counterparts in less densely populated ones. It further suggests that the surviving generalists will narrow the focus of their lobbying activities to fewer issues and to those issues on which they have a comparative advantage. We test both hypotheses directly by looking at the mobilization and lobbying focus of U.S. state Chambers of Commerce and find evidence that even these old bulls of the lobbying pasture are powerfully influenced by competition among business interest organizations