In the race are two congressman, a former state treasurer, a former state senator and a businessman, among others.
It's been at least a decade since Democrats faced such a crowded primary field, and the Republican race is likely to heat up too. Meet some of the front-runners.
Democratic lawmakers are suing President Donald Trump over foreign money flowing into his global business empire.
The assailant, prepared with "a lot of ammo," fought a gun battle with police before he, too, was shot and later died.
In modern times, private bills are mostly used to help undocumented immigrants receive temporary stays while federal officials review their cases.
The Jefferson County Democrat joins a growing field of candidates who want to replace Gov. John Hickenlooper next year.
Town halls have become outlets for public anger nationwide with the new administration, and some Colorado constituents aren't happy their elected officials are in unavailable.
Members are under pressure from liberal groups to schedule constituent events, but only a few have put any on their calendars.
Read the full statements on Trump's executive order on immigration from Colorado's congressional delegation.
Jordan MacTaggert and Levi Shirley died over the summer in Syria.