I'm participating in the coalition as a CMC member and volunteer, and as a representative of my own org, The Next Summit; Both organizations are part of the broader coalition of 32-ish groups endorsing the bill (the number keeps rising). The CMC's Conservation Staff have played a central role as a convener and coalition-builder; their team is really to thank for keeping it alive and putting in the legwork. I helped with some initial policy research on the issue, and now I've been tasked with updating online communities impacted by the issue and starting some initial grassroots organizing work for future initiatives.
The full list of non-profits, businesses, and public sector supporters, as of now, includes:
Access Fund
American Alpine Club
Bicycle Colorado
Boulder Climbing Community
Central Colorado Cattlemen's Association
Colorado Civil Justice League
Colorado Farm Bureau
Colorado Fourteeners Initiative
Colorado Mountain Club
Colorado Springs Utilities
Colorado Water Congress
Continental Divide Trail Association
International Council of Shopping Centers
International Mountain Biking Association
Mosquito Range Heritage Initiative
The Next Summit
Open Boulder
Outdoor Alliance
Park County Board of Commissioners
People for Bikes
Rec Law
Rocky Mountain Farmers Union
Rocky Mountain Wild
The Town of Alma
The Wilderness Society
Trails and Open Space Coalition
Trust for Public Land
Ute Water Conservancy District
Uncompahgre Valley Water Users Association
Winter Wildlands Alliance