Former Denver Mayor Wellington Webb formally endorsed Democrat Jason Crow in the 6th Congressional District primary on Friday, calling the attorney and Army Ranger combat veteran “an effective leader who can build coalitions and unify the community to get things done.”

Crow is one of three Democrats running in a primary for the seat held by five-term incumbent U.S. Rep. Mike Coffman, an Aurora Republican.

Noting that he’s known Crow for more than a decade, Webb wrote in a Facebook post announcing his endorsement that he believes Crow has the best chance to defeat Coffman in the battleground suburban district.

Webb, who served three terms as mayor of Denver, has been a towering political figure in Denver and nationally in the Democratic party for decades, starting in the 1970s.

After serving two terms in the state House of Representatives, Webb was appointed regional director of the U.S. Department of Health, Education and Welfare under President Jimmy Carter and then served as director of the Colorado Department of Regulatory Agencies under Gov. Dick Lamm. He was elected to one term as Denver’s auditor before winning election as the city’s first African-American mayor. He runs Webb Group International, a political and government relations consulting firm.

“From his leadership in helping to bring the new VA hospital in Aurora to his pro-bono work helping homeless and at risk veterans, Jason is a dedicated Coloradan who I know will fight for us in Congress – after all, he’s been standing up for his community his entire life,” Webb wrote in his endorsement. “And now, at a time when justice and rule of law are at risk with every passing day, Colorado needs a leader who will go to Washington and help restore order to Congress. From his combat tours in the Army to his work as an attorney, Jason has spent his life turning words into action. He is the Democrat who will take down Mike Coffman next November and bring Colorado values back to the 6th Congressional district. I enthusiastically endorse his candidacy.”

The other Democrats running for the seat are Levi Tillemann, a clean-energy expert and former Obama administration official, and David Aarestad, an attorney and one-time candidate for the Cherry Creek School Board.