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Interest-Group System

Last Updated: 2021

An “interest group system” refers to the totality of organized interests in a larger political system. Each state government, many local governments, and the federal government has its own “interest group system.” Further, these systems are connected in various ways.

The American federal system is composed of far more than 50 interest-group systems: the federal government system, 50 state systems, about five territorial systems, such as that of Puerto Rico, and numerous local systems, especially in large cities and metropolitan areas. Each is different in its composition and impact. How do national and state/territorial interest-group systems compare? How do states compare with one another? And how and why do actors join forces across these interest-group systems and intervene from one system to another? In answering these questions, governmental entities can be sources as well as targets of influence efforts. Governments lobby governments, as do their agencies, officials, and their associations. Local governments routinely seek to influence their state legislature and governor, and those legislatures and governors try to influence the U.S. Congress and the president.

There are important differences among these various systems today in their composition, influence, and regulation.


Historically, state-based interest-group systems varied widely in their size and composition. Those variations have diminished somewhat over the 1980s as the number and diversity of interests in many states have increased; however, variations persist. For example, the number of interest groups by state ranges from over 3,000 in New York to barely 300 in Hawaii and Alaska. Population size matters of course, but so do other factors.

Virginia Gray and David Lowery developed a model to explain these variations based on economic, demographic, and other differences (2001). For example, some states are rich in an extractive natural resource (e.g., coal) with powerful mining interest groups, and those groups become more active when mining legislation comes before the legislature. Likewise, some states have a larger share of a certain demographic group such American Indians, Hispanics, or retired persons who have larger and more active interest groups as a result.

Clive Thomas, Ronald Hrebenar, and Anthony Nownes identify three other factors explaining differences in the size and diversity of interest groups. States with an individualistic political culture are more receptive to the notion of a plurality and even cacophony of interest voices; states with a moralistic political culture see joining common causes as a civic responsibility; states with a diversified population or economy attract more interest groups; and states with a weaker political party system tend to attract interest groups as do states with an initiative process (2009).

Historically, some of these factors also explained differences between national and state systems. The federal government has no referendum or initiative process and no judicial elections. When education, insurance, and real estate were largely regulated by the states, there was less reason for these sectors to lobby in Washington, DC. Interest groups representing single industries like gambling and mining were more prevalent in states where those industries had a large presence as were organizations representing larger than average demographic groups such as retired persons in Florida.

Since the late 1960s, the federal government has become more involved in many public policy areas that were traditionally state based. At the same time, the states have assumed more responsibility for implementing more federal public policies, and some states are regulating a wider range of interests from business to the environment.

As a result, many interest groups must develop bifocal lobbying. Traditional state-centered policy fields such as education, real estate, and insurance are now among the 20 largest categories of interest-group spenders in lobbying Congress as are groups representing retired persons. Conversely, multi-national corporations and Washington-based national interest groups need to monitor state legislation and often lobby in a few key states where legislation or regulation threatens their interests (e.g., automobile manufacturers lobbying more intensely in California).


The increased diversity of interest groups in many states along with the rise of single-issue and so-called “public interest” groups has somewhat diluted the influence of single large corporations and interest groups in the states. However, state interest-group systems differ in the extent of overall interest-group dominance in their state. Thomas, Hrebenar, and Nownes analyzed changes in these differences from 1960 to 2000. This study classifies the 50 states by the overall impact of interest groups in their state. The authors distinguish five categories. At one extreme, the “dominant” category includes only a handful of states (such as Alabama, Florida, Hawaii, and Nevada) in which interest groups are “the major force in state politics.” At the other extreme, a “subordinate” system is one in which interest groups are “consistently subordinated” to other forces in the state’s political system. No state has been in this category since the 1980s. In between, a “complementary” system has interest groups as one of “many forces of power” in the state. At either end of the middle are “dominant/complementary” and “complementary/subordinate” systems in which the state alternates between or transitions from one category to the other (Thomas, Hrebenar, and Nownes, 2009). Although states can migrate from one category to another, most states tend to fall into the “dominant/complementary” or “complementary” categories. This is a major historical change. Before 1960, most states would have fallen into the dominant or dominant/complementary categories. The trends toward interest-group proliferation and specialization and increased diversity in state populations and economies help explain this movement.


Part of an interest-group system is government regulation of interest groups and lobbying in that system. These regulations include provisions attached to the incorporation of interest-group organizations, the registration of lobbyists, and the reporting of lobbying and campaign-finance activities.

Lobbying in the states is a small industry that reached $1 billion in 2005 by over 40,000 registered lobbyists representing 50,000 organizations (Thomas, Hrebenar, and Nownes, 2009). All states now require lobbyists and interest groups to register, although the definitions of “lobbyist” vary from broad to narrow. All states require reporting of lobbying activities, but there is considerable variation in what must be reported and how often. Some states also require disclosure of who receives the money. Some states restrict what can be given or received. In some states, nothing can be given or received (not even a cup of coffee). Generally, states with the strictest lobbying laws are those historically or culturally inclined to do so, or those that experienced a level of political scandal or corruption that prompted “enough is enough” laws.

Notwithstanding their variations, most states have stricter lobbying laws than federal laws. Many states have stricter campaign-finance laws as well, and some have public financing of gubernatorial and or state legislative campaigns. This subject is beyond the scope of this entry, but suffice it to say that lobbying is an important way in which interest groups seek to influence government decisions by influencing the officials who make those decisions. Election-campaign contributions can be important too, but most interest groups do not make such contributions in state races.

SEE ALSO: Interest Groups


Virginia Gray and David Lowery, “The Institutionalization of State Communities of Organized Interests,” Political Research Quarterly 54 (2001): 265–284 and Clive Thomas, Ronald Hrebenar, and Anthony Nownes, “Interest Group Politics in the States: Four Decades of Developments, 1960 to the Present,” Book of the States: 2008 (Lexington, KY: Council of State Governments, 2009), p. 322 – 331.