In one of the most closely watched primary races of the evening, Sen. Michael Bennet won the Democratic Senate nomination.
Bennet beat former state house speaker Andrew Romanoff. With 67 percent of the vote counted, Bennet had a comfortable lead of 54.1 percent versus 45.8 percent for Romanoff.
The race was seen as a referendum on incumbents as well as an early test of former President Bill Clinton's strength as an endorser.
The ex-president supported Romanoff. Meanwhile President Barack Obama backed Bennet who is in the Senate only because after his election to the presidency, Obama chose Bennet's Senate predecessor Ken Salazar to be his Interior Secretary.
The winner of the Republican Senate primary was still unclear as of this writing, with Weld County District Attorney Ken Buck holding a small lead over Jane Norton, a former lieutenant governor.