Denver Democrats Wellington and Wilma Webb formally endorsed former state Sen. Mike Johnston for governor on Thursday, his campaign announced.

“This is a time for new and bold leadership in Colorado,” said Wellington Webb, a former three-term mayor of Denver. “From watching his work over the past seven years, I know Mike has the vision and leadership to shape the future of Colorado for all its residents.”

Johnston is one of four Democrats running to take term-limited Gov. John Hickenlooper’s place after next year’s election. The others with hats in the ring are U.S. Rep. Jared Polis, former State Treasurer Cary Kennedy and businessman Noel Ginsberg. In addition, Hickenlooper’s lieutenant governor, former Kaiser Permanente executive Donna Lynne, declared this week she’s exploring whether to join the primary field.

The Webbs – sometimes referred to as the Wilmingtons – have been towering political figures in Denver for decades, starting in the 1970s.

After serving two terms in the state House of Representatives, Wellington Webb was 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 served one term as Denver’s auditor before winning election as the city’s first African-American mayor.

Wilma Webb served from 1980 to 1993 in the Colorado House and was the first African-American representative elected to the powerful Joint Budget Committee. She also spearheaded Colorado’s adoption of Dr. Martin Luther King, Jr.’s birthday as a state holiday.

“As a representative, I knew the importance of building coalitions across the state,” Wilma Webb said in a statement endorsing Johnston. “From the day he opened his office in the heart of Northeast Denver, I’ve been impressed by his deep commitment to our community and to building bridges to communities across Colorado.”

Johnston, who maintained a community office in his Senate district during his tenure in office, noted that Wellington Webb won his first run for mayor by walking across Denver and that Wilma Webb “first turned Northeast Denver into a political force in the statehouse.”

“I have long been grateful to the Webbs for their counsel and wisdom over the years, and now I am humbled by their faith in me and their belief in a brighter future for Colorado,” he said.

Wellington Webb, who runs Webb Group International, a political and government relations consulting firm, added, “I’ve been at this for 40 years, and Mike is the kind of candidate who doesn’t come around very often. He knows all parts of this state and understands the needs of both the young men outside his community office trying to find work and the single mom in Gypsum trying to put her kids through college. Mike is exactly the leader Colorado leads now”