This is the second in a series of race rundowns designed to give subscribers a quick snapshot of what's happening in each district in 2018. Throughout the cycle, watch for our detailed analysis of the most closely-fought races in our competitive race overviews. Individual race pages will be updated as developments warrant, and be sure to bookmark our ratings to keep track of the latest changes.

Colorado

CO-01: Diana DeGette (D) - Central: Denver Solid Democratic. This Denver district is the safest Democratic seat in the state and DeGette is well-entrenched.

CO-02: OPEN Polis (D) - North: Boulder, Ft. Collins Solid Democratic. Polis's bid for governor should be setting off an avalanche of interest in this very liberal Boulder seat, but for now the all-important Democratic primary is in a holding pattern. Former regent and top state regulator Joe Neguse is the nominal frontrunner for now over businessman Ken Toltz and former Boulder Democratic chair Mark Williams. But Shannon Watts, a founder of the gun control group Moms Demand Action, is likely to run and would be a serious candidate.

More from the Cook Political Report