Businessman Dan Maes rode support from tea party groups to claim Colorado's Republican gubernatorial primary, defeating former U.S. Rep. Scott McInnis.
McInnis, who served six terms in Congress, failed to recover after it was revealed that he plagiarized parts of a water study for which he was paid $300,000 by a Colorado foundation.
Maes overcame his own troubles in winning Tuesday: He was fined $17,500 for campaign finance violations and drew criticism over remarks that he would fire thousands of state workers.
The rocky campaigns prompted former U.S. Rep. Tom Tancredo to bolt from the party and run for governor on the American Constitution Party ticket.
Denver Mayor John Hickenlooper will be the Democrat on the November ballot. He faced no opposition for his party's nomination.
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