Colorado voters have never before faced as many congressional primaries as they do this year.
Republican Doug Lamborn has become accustomed to facing primaries in the Colorado Springs-based 5th Congressional District - he's only run for re-election once since winning the heavily Republican seat in 2006 without having to navigate one - but primaries tend to be the exception. This year, they're the rule.
There's a primary in every one of Colorado's seven congressional district but one - the 7th, covering the Denver area's western and northern suburbs, where U.S. Rep. Ed Perlmutter will be facing Republican Mark Barrington in November in the Arvada Democrat's bid for a seventh term.
Lamborn is attempting to win a seventh term against four primary challengers - El Paso County Commissioner Darryl Glenn, state Sen. Owen Hill, former Green Mountain Falls Mayor Tyler Stevens and former Texas judge Bill Rhea.
The Republicans gunning for Lamborn's job populate the full range of the current GOP, with Glenn and Hill staking out the far right, Stevens touting his experience as a businessman and decades of community service and Rhea running against the direction the party has taken since Trump took it over.
Glenn and Hill criticize the incumbent as ineffectual, but Lamborn points to his consistent top ranking on conservative scorecards and his success bringing a veterans cemetery to the region, as well as increased troop levels at the district's military bases and long-sought funding for transportation needs.
Democrat Stephany Rose Spaulding is her party's nominee for the 5th District seat.
Up the road, U.S. Rep. Diana DeGette is running for a 12th term in the safely Democratic Denver-based 1st Congressional District against political newcomer Saira Rao, a former Wall Street attorney and founder of a company that packages children's books that emphasize diverse points of view. It's only DeGette's third primary since she won the seat in 1996.
Meanwhile, Republican Casper Stockham is mounting his second bid for the Denver-based seat.
The road to a Democratic majority in the House likely winds through the suburban 6th Congressional District, which includes Aurora and points north and south.
In the nearly evenly divided battleground district, the forces that defined the Democrats' 2016 presidential election are pitted against each other as establishment-backed attorney and Army Ranger combat veteran Jason Crow faces the more left-wing Levi Tillemann, a clean energy expert and author.
They're vying for the chance to run against U.S. Rep. Mike Coffman, the Aurora Republican and Army and Marine Corps veteran who has held the seat since 2008.
Three Democrats are vying for the chance to take on another Republican incumbent targeted by national Democrats, U.S. Rep. Scott Tipton, who represents the 3rd Congressional District, which covers much of the Western Slope, Pueblo and the San Luis Valley.
Former state Rep. Diane Mitsch Bush, D-Steamboat Springs, got in the race first but is facing a determined challenge for the nomination from Carbondale rancher and water attorney Karl Hanlon. Arn Menconi, a former Eagle County commissioner and the Green Party's 2016 nominee for the U.S. Senate, is also on the ballot.
In the open Boulder and Larimer County-based 2nd Congressional District, former University of Colorado Regent Joe Neguse, an attorney and the Democrats' nominee for secretary of state in 2014, is facing a primary from the party's left flank mounted by Mark Williams, an Air Force fighter pilot veteran, entrepreneur and former chair of the Boulder County Democratic Party. Peter Yu is the GOP nominee for the seat.
In the sprawling 4th Congressional District, which stretches from Greeley to Douglas County and covers the Eastern Plains, two Democrats who also happen to be veterinarians - Karen McCormick of Longmont and Chase Kohne of Castle Rock, both political newcomers - are squaring off for the chance to take on Republican U.S. Rep. Ken Buck, the former prosecutor serving his second term in Congress.