ALBUQUERQUE, N.M. (AP) — U.S. Sens. Tom Udall and Martin Heinrich are trying again to make the Valles Caldera National Preserve a national park.

The New Mexico Democrats on Tuesday reintroduced legislation to transfer management of the preserve to the National Park Service. Udall and retired Sen. Jeff Bingaman first proposed the transfer in 2010 in hopes of getting more consistent funding to preserve and improve the area and increase recreation.