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.
Modern liberalism in the United States
In the 1950s and 1960s, both major US political parties included liberal and conservative factions. The Democratic Party had two wings: on the one hand, Northern and Western liberals, on the other generally conservative Southern whites. Difficult to classify were the northern big city Democratic "political machines". The urban machines had supported New Deal economic policies, but faded with the coming of prosperity and the assimilation of ethnic groups; nearly all collapsed by the 1960s in the face of racial violence in the cities