The court issued the final word in the redistricting battle on Monday.
The ruling upholds a decision from Denver District Judge Robert Hyatt in favor of changing Coffman's district by moving Republican-leaning portions of Douglas County into the Eastern Plains seat held by Republican Rep. Corey Gardner. The map also puts the City of Aurora entirely in Coffman's seat, instead of being split between two districts.
Much of Aurora was in Rep. Ed Perlmutter's (D-Colorado) 7th District before the change. His division of registered voters in different parties is staying nearly the same, with Democrats holding a slight edge.
The GOP has held Coffman's 6th District since it was created after the 1980 election.
Republicans had 46 percent of the district's voters, beating Democratic registration by 20 points.
The new map gives Republicans, Democrats, and unaffiliated voters each roughly a third of the registered electorate.
By voter registration, it will be the most competitive district in the state.
"[Coffman] is really going to have to run hard as opposed to be sort of an incumbent and be able to relax," 9NEWS Political Analyst Floyd Ciruli points out.
"I'm disappointed that I'm losing so many of my constituents but I'm excited about running in the new district," Coffman said in a written statement. "I grew up in Aurora, went to school in Aurora, started a small business in Aurora, and I still live in Aurora. I have the home field advantage and a testament to my strength as a candidate is that there are no Democrats challenging me who live in the new district."
Republicans argued the Democratic map made unreasonable changes to make more races competitive. Democratic attorney Mark Grueskin says the decision sends a message that members of Congress can he held accountable with competitive districts.
Competition is exactly what the Democrats wanted, since they don't have a majority of Colorado's seats in Congress.
With this change, there's more of a chance for Democrats to change that.
The decision will not be appealed to the U.S. Supreme Court.
Below is a table showing the breakdown of registered voters in Colorado's newly redrawn congressional districts. Source: Heizer | Paul | Grueskin LLP.
(KUSA-TV © 2011 Multimedia Holdings Corporation with The Associated Press)