Colorado Attorney General Phil Weiser has won the Democratic gubernatorial primary, NBC News projects, defeating incumbent Senator Michael Bennet by 10 percentage points with over 80% of votes counted. Weiser's victory marks a significant upset against a 17-year Senate veteran who previously sought the Democratic presidential nomination in 2020.

Both candidates campaigned heavily on anti-Trump messaging, but Weiser successfully positioned himself as the more aggressive challenger. He repeatedly attacked Bennet for voting to confirm eight of Trump's Cabinet nominees, painting him as a Washington insider. Meanwhile, Bennet criticized Weiser for not joining lawsuits against the Trump administration during its first term, despite Weiser filing or joining at least 50 suits overall.

Weiser's win reflects growing Democratic frustration with establishment figures, suggesting Colorado voters prefer a more confrontational approach to opposing federal policies. As a former University of Colorado Law School dean, Weiser brings different credentials than Bennet's long federal tenure. His attorney general record of litigation against the Trump administration resonated more strongly than Bennet's legislative experience.

The Republican primary remained too close to call Tuesday night, with State Sen. Barb Kirkmeyer narrowly leading Marine veteran Victor Marx. Weiser enters the general election as the clear front-runner in a state that hasn't elected a Republican governor in over two decades.