Some in the United States see parties like the Green Party or Libertarian Party as a detrimental part of a major election cycle, siphoning off votes from their close ideological "cousins" and potentially costing the election. Sociologically, however, the presence of more than two parties—a multiparty system—is vital in order to:

foster diverse interests and allow for the representation of more radical alternatives

Explanation:

A multi-party system is a political arrangement that is set up to provide the ability for multiple political parties to take control of the government independently or in a coalition. In the American context where two parties dominated the political stage, a multi-party system ensured that regional and local parties have a fair chance of winning elections and more attention will be given to more views.