<P> The Green Party in the United States has won elected office mostly at the local level; most winners of public office in the United States who are considered Greens have won nonpartisan - ballot elections (that is, elections in which the candidates' party affiliations were not printed on the ballot). In 2005, the Party had 305,000 registered members in the District of Columbia and 20 states that allow party registration . During the 2006 elections the party had ballot access in 31 states . In 2017, Ralph Chapman, a Representative in the Maine House of Representative switched his association from Unaffiliated to the Green Independent Party . </P> <P> The United States Green Party generally holds a left - wing ideology on most important issues . Greens emphasize environmentalism, non-hierarchical participatory democracy, social justice, respect for diversity, peace and nonviolence . As of 2016, it is the fourth largest organized political party in the United States . </P> <P> The Constitution Party is a small national right - wing political party in the United States . It was founded as the U.S. Taxpayers Party in 1992 by Howard Phillips . The party's official name was changed to the Constitution Party in 1999; however, some state affiliate parties are known under different names . </P> <P> The Constitution Party is strongly pro-life (i.e. opposed to abortion), and supports gun rights, and restrictions on immigration . It calls for protectionist trade policies . </P>

What is the natural number of political parties in the american political system