Minor political parties can play an important role in a county's politics by virtue of their ability to influence the controlling party to adopt some of their platforms. Because they are not guaranteed a good chance of winning a major election and becoming a controlling party, minor political parties can be inventive, take chances and promote a radical idea to a much greater degree than established major parties would. In this respect, minor political parties can introduce into the political spectrum new viewpoints and approaches that major parties may have never introduced on their own.
In governments based on a multiparty system, minor parties have a chance of becoming part of a coalition when no single major party has the capacity to control the government on its own. In such multiparty systems, minor parties can help to provide a coalition with a better chance of developing a more effective power block in governing. Countries such as Brazil, Finland, Germany, Israel and Italy have made effective use of multiparty coalitions in their democratic processes.
In the United States, which is a two-party system, no minor political party has ever gained control of the government. There have, however, been notable instances of a minor party exerting enough influence to achieve its aims through legislation. The early 20th-century Progressive Party, for example, never won control of the U.S. government, but by exerting its influence and promoting its causes of a minimum wage and other economic and social reforms, the party eventually saw many of its aims achieved through the legislative process.