This word, especially in the U.S., has acquired a sinister meaning. See quotations.

1

1646.  Lewis, though he were then in truce and league with him, was meerly a Politician, and studied only his owne ends.—G. Buck, ‘Richard III.,’ i. 17. (N.E.D.)

2

1841.  A Whig Editor, a bar-room wrangler, a stump orator, a noisy, brawling, pot-house politician.—Mr. Gordon of N.Y., House of Repr., Aug. 25: Cong. Globe, p. 264, App.

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1862.  Not pot-house politicians only, but profound thinkers, declared the Government permanently crippled.—Mr. Samuel Shellabarger of Ohio, the same, Feb. 6: id., p. 690/1.

4

1862.  

        Queer politicians, though, for I ’ll be skinned
Ef all on ’em don’t head aginst the wind.
Lowell, ‘Biglow Papers,’ Second S., No. 6.    

5

1879.  The word ‘politician’ is used in a bad sense in America, as applied to people who make politics a profession, and are skilled in the art of ‘wire-pulling’ and such practices.—Sir G. Campbell, ‘White and Black,’ p. 68. (N.E.D.)

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