Two-party system
Third parties, meaning a party other than one of the two dominant parties, are possible in two-party systems, but they are often unlikely to exert much influence by gaining control of legislatures or by winning elections. While there are occasional opinions in the media expressed about the possibility of third parties emerging in the United States, for example, political insiders such as the 1980 presidential candidate John Anderson think the chances of one appearing in the early twenty-first century is remote. A report in "The Guardian" suggested that American politics has been "stuck in a two-way fight between Republicans and Democrats" since the Civil War, and that third-party runs had little meaningful success.
Greens/Green Party USA
The source of the rift between the two national Green parties is a matter of contentious debate. Some point to differences of political philosophy or views on the proper structure of the party or attitudes toward elections, while others suggest it was more about personality conflicts, turf struggles, and poor communication leading to concerns about financial and political accountability, or perhaps the 1991 name grab or the inaccurate G/GPUSA FEC filing in 1995. It is important to note that the heated debates and the fighting that was waged for several years at the national level (and among Greens within a few states, such as New York, Missouri, California and New Jersey) seemed largely irrelevant to the vast majority of grassroots Greens, who preferred to devote their energies to local organizing.