MUGWUMP

n. politician who flaunts his independence; bolter of the Republican Party during the United States presidential election of 1884; politically neutral or uncommitted person

The Mugwumps were Republican political activists who supported Democratic candidate Grover Cleveland in the United States presidential election of 1884. They switched parties because they rejected the financial corruption associated with Republican candidate, James Blaine. In a close election the Mugwumps supposedly made the difference in New York state and swung the election to Cleveland.
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Noun
1. someone who bolted from the Republican Party during the U.S. presidential election of 1884
(hypernym) politician, politico, pol, political leader

Noun
1. a neutral or uncommitted person (especially in politics)
(synonym) independent, fencesitter
(hypernym) individualist
(classification) politics, political science, government

(n.)
A bolter from the Republican party in the national election of 1884; an Independent.
  

Synonyms and related words:
Fabian policy, Micawberism, Milquetoast, anythingarian, apostate, backslider, backwardness, big boy, big chief, big shot, bigwig, bolter, collaborationist, collaborator, convert, defector, deserter, dilatoriness, fence-sitter, fifth columnist, free lance, free spirit, free trader, freethinker, heavyweight, hesitation, high-muck-a-muck, hold-off, independent, individualist, isolationist, jellyfish, latitudinarian, laxness, leader, liberal, libertarian, libertine, lion, nabob, neuter, neutral, nonpartisan, nothingarian, procrastination, proselyte, quisling, recidivist, recreant, remissness, renegade, renegado, renegate, reversionist, rugged individualist, runagate, schismatic, seceder, secessionist, separatist, shilly-shally, slackness, slowness, stall, strikebreaker, swing vote, temporization, tergiversant, tergiversator, third force, third world, traitor, turnabout, turncoat, turntail, uncommitted voter, waverer, weakling, wobbler