Richard F. Pettigrew (1848-1926)? Truth be told, he was outspoken and radical for his times, and the role he played on the national stage is largely forgotten.
Pettigrew was a lawyer and land surveyor, two professions which dovetail nicely into real estate promotion and development. He figured prominently in the growth of Sioux City, South Dakota. As a young man, he involved himself in local Republican politics and upon statehood became South Dakota's first senator in Washington.
Pettigrew soon soured on the crony capitalism he discovered in the nation's capital. He bolted the Republican Party over the currency issue at the 1896 Convention. He opposed McKinley on foreign policy, seeing in our pursuit of war with Spain the birth of an American Empire. Pettigrew was still technically a Republican senator when he voted against the illegal annexation of Hawaii in 1898--the only one of his party to do so. The GOP was glad to be rid of him when his term ended in 1900. Pettigrew aligned himself with the Populists, then the Democrats (though he never trusted Woodrow Wilson,) and ultimately the Socialists.
The defining moment of his career, however, came in 1917. He opposed our entry into the First World War, seeing it as capitalist manipulation bent on enriching the wealthy elites. He urged all young men to evade the draft. Woodrow Wilson's adminstration brought a felony indictment against him for violating the Espionage Act of 1917. Socialist leader Eugene V. Debs was already serving a ten-year prison sentence under the same charge. Pettigrew was not without resources, however, and enlisted Clarence Darrow to lead his defense. The charges against him were eventually dropped.
Jeff Taylor over at the Front Porch Republic (here) describes Wilson's Espionage Act as the "bad gift that keeps on giving...enshrining the principle that speech is free except when the government deems it unhelpful." (He also noted that Woodrow Wilson was our worst President ever. I would qualify that judgment only slighty, for he is certainly among the bottom three.)
In 1922, Pettigrew published Imperial Washington, with the inside blurb written by Lenin himself. At his death in 1926, Pettigrew willed his home to the City of Sioux Falls for use as a museum, with the stipulation that the framed copy of his federal indictment must be prominently displayed next to his framed copy of the Declaration of Independence.