Rebellious Colorado voters in both parties rejected insiders Tuesday as Democrats and Republican began choosing candidates for top races this fall.

Democratic Sen. Michael Bennet lost precinct straw polls to former state House Speaker Andrew Romanoff. Democrats statewide griped that party leadership has failed to deliver progressive legislation since taking control of Congress and the White House.

And on the Republican side for Senate, former Lt. Gov. Jane Norton was locked in a tight race with Weld County District Attorney Ken Buck and former state senator Tom Wiens. Norton far outpaced other Republicans in fundraising, but she garnered less than 40 percent of the total Republican vote.

The caucuses are the first step for party nominations in Colorado; the nominees won't be picked until Aug. 10 primaries.

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