<P> In some countries like the United States, parties with low win probability also face frequent exclusion from major debates and media coverage and denial of ballot access as well as hamstrung campaign budgets . </P> <P> In U.S. politics, a third party is a political party other than the Democrats or Republicans, such as the Libertarians and Greens . The term "minor party" is also used in a similar manner . Such political parties rarely win elections, as proportional representation is not used in federal or state elections, but only in some municipal elections . </P> <P> A similar situation occurs with the presidential Electoral College, where Electoral College votes are often given the candidate who receives a plurality of the vote, thus bringing up accusations that certain third party presidential candidates are "spoiling" the election or splitting up segments of voters . </P> <P> Third parties usually have little chance of forming a government or winning the position of head of government . Nevertheless, there are many reasons for third parties to compete . The opportunity of a national election means that attention will be paid to the positions of third parties . The larger parties might be forced to respond and adapt to their challenges, and often the larger parties copy ideas from them . Most third parties try to build their support to become one of the dominant parties, as the Labour Party in Britain did . </P>

All of the following are reasons why third parties tend to remain minor in the us except