President Barack Obama has made a splash declaring some federal lands in the west national monuments, making them off-limits to development.

Now, a push is on to have a West Texas range declared a national monument as one of Obama's final acts in the White House.

Preserving the Castner Range and Franklin Mountains Wilderness, which are just northeast of El Paso near Fort Bliss military installation, is the focus of a long-running effort by conservationists.

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U.S. Rep. Beto O'Rourke, D-El Paso, has asked Obama to declare the area a national monument before he leaves office on Friday, Jan. 20, 2017.

So far, more than 35,000 people have signed a petition to preserve the mountains, which were once used as a firing range by soldiers at Fort Bliss.

Obama set off a firestorm of criticism in December when he declared Bears Ears National Monument in Utah and Gold Butte National Monument in Nevada. Local politicians were upset Obama acted by presidential order and didn't allow state officials to have the final say.

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Will Castner Range National Monument become a reality?

O'Rourke told The El Paso Times that having the 7,000 acres declared a national monument before Obama leaves office seems unlikely, But, O'Rourke said, senior officials have told him they are likely to set in motion a process “that would be very difficult to be undone.”

In politics, especially as a president heads out the door, anything is possible.

>>>Click through the above gallery to see photos from the Castner Range as well as photos from Big Bend National Park in West Texas.