WordNet (r) 3.0 (2006):

political party
    n 1: an organization to gain political power; "in 1992 Perot
         tried to organize a third party at the national level"
         [syn: party, political party]

Moby Thesaurus II by Grady Ward, 1.0:

59 Moby Thesaurus words for "political party":
   American Party, Anti-Monopoly Party, Bull Moose Party,
   Communist Party, Conservative Party, Constitutional Union Party,
   Democratic Party, Democratic-Republican Party, Farmer-Labor Party,
   Federalist Party, Free Soil Party, Greenback Party,
   Know-Nothing Party, Labour Party, Liberal Party,
   Liberal Republican Party, Liberty Party, National Republican Party,
   Populist Party, Progressive Party, Prohibition Party,
   Republican Party, Socialist Labor Party, Socialist Party,
   Socialist Workers Party, Tammany Hall, Tory Party, Whig Party,
   breakaway group, camp, caucus, city hall, division, ethnic group,
   faction, interest, interest group, machine, major party,
   minor party, minority group, multiple party system, offshoot,
   one-party system, opposition party, party, party in power,
   political machine, pressure group, sect, side, silent majority,
   splinter, splinter group, splinter party, third party,
   two-party system, vocal minority, wing