quality:correction, structural:reformatting, structural:expansion
United States

Modern American politics, in particular the electoral college system, has been described as duopolistic since the Republican and Democratic parties have dominated and framed policy debate as well as the public discourse on matters of national concern for about a century and a half. Third parties have encountered various blocks in getting onto ballots at different levels of government as well as other electoral obstacles, such as denial of access to general election debates. Since 1987, the Commission on Presidential Debates, established by the Republican and Democratic parties themselves, supplanted debates run since 1976 by the League of Women Voters. The League withdrew its support in protest in 1988 over objections of alleged stagecraft such as rules for camera placement, filling the audience with supporters, approved moderators, predetermined question selection, room temperature and others. The Commission maintains its own rules for admittance and has only admitted a single third-party candidate to a televised debate, Ross Perot, in 1992.