U.S. Rep. Jared Polis of Boulder and three other members of Colorado’s House delegation have signed onto the latest effort to urge Congressional leaders to find a way to permanently reauthorize and fully fund the Land and Water Conservation Fund.

But missing from the letter: the only Republican in Colorado’s House delegation – U.S. Rep. Mike Coffman of Aurora – who has co-sponsored legislation that would do exactly what the letter asks.

The fund, which largely draws on federal offshore drilling, has provided more than $267 million for recreation and conservation projects in Colorado.

Polis – the Democratic candidate for governor – and U.S. Rep. Scott Tipton of Cortez both announced last week they would support full funding, estimated at as much as $900 million per year, plus permanent reauthorization of the conservation fund.

The program was allowed to lapse in 2015 after conservative critics said it funded too many federal projects rather than local ones but was then temporarily re-authorized. That re-authorization expires Sept 30.

The letter was released Tuesday by Polis’ office and sent to Speaker of the House Paul Ryan of Wisconsin and House Minority Leader Nancy Pelosi of California.

It doesn’t identify a specific piece of legislation. There have been numerous attempts to find a way to save the LWCF, but the signatories could not agree on a specific bill. Instead, it asks the leadership to “work with us and pass legislation” that will make the fund’s future a reality.

“In Colorado, you can barely throw a stone without hitting an LWCF investment,” Polis said in the letter, noting that Colorado’s “crown jewel” parks have all benefited from the LWCF, including Rocky Mountain, Mesa Verde, Black Canyon of the Gunnison and Great Sand Dunes national parks.

The Sand Dunes are set for a $7 million investment from LWCF to purchase a nearby property, a historical working ranch complete with a bison herd that is run by The Nature Conservancy. The ranch would be transferred to the National Park Service, “permanently protecting the historic and archaeological sites on the property and the critical groundwater of the sand dune ecosystem,” according to a report issued Wednesday by the Center for Western Priorities.

In addition to Polis and Tipton, Reps. Ed Perlmutter and Diana DeGette also are signatories.

But one signature that is notable by its absence is Coffman’s, who along with Polis, Perlmutter and DeGette, is a co-sponsor of a major House measure – HR 502 – that would do exactly what the letter calls for and that has 232 co-sponsors. The bill has languished for months in a subcommittee chaired by U.S. Rep. Doug Lamborn of Colorado Springs, and isn’t viewed as the pathway for the LWCF’s survival.

Coffman – who is in a competitive race for re-election against Democrat Jason Crow – told Colorado Politics that he is “proud to support the permanent reauthorization of the Land and Water Conservation Fund. The funding will help states protect their natural treasures and wildlife for generations to come. This bill not only has an important environmental impact, but it is also important to Colorado’s economy in promoting outdoor recreation.”

More likely is that the LWCF could be attached to one of several spending bills that must be acted on when Congress returns from its August recess Tuesday. The best candidate appears to be H.R. 6147, referred to as a mini-omnibus bill that provides appropriations for several federal agencies, including the Department of the Interior.