Time is running out on a deal to secure the largest expansion of Yosemite National Park since 1939, and one man appears to be standing in the way: local congressman Tom McClintock.

Declaring his distrust in the National Park Service, the tea party Republican from Granite Bay is at odds with local Republican state legislators and the Mariposa County Board of Supervisors over efforts to add a scenic parcel of land on Yosemite’s western boundary now owned by a Bay Area conservation group. The deal is even becoming a campaign issue in this rugged part of California as McClintock fights for re-election against a fellow Republican.

If a deal isn’t reached by the end of the year, the small nonprofit group that owns the land says it will have to sell. And the land is zoned for construction of up to 19 homes.

“We’ve held this for 10 years and have the holding costs — the property taxes, management and upkeep, things of that nature,” said Laurie Wayburn, president of the Pacific Forest Trust in San Francisco.

“We are now at a point where we are faced with the hard choice of asking: ‘Are we going to be able to keep holding onto it or are we going to have to sell it to the private market?'”

In 2004, the trust bought the land — a scenic landscape near El Portal that is thick with incense cedar, white fir and sugar pine trees, with breathtaking views — from a family that had owned it since 1925.

The purchase, praised by the park’s superintendent, was intended to expand Yosemite to the original boundaries that conservation pioneer John Muir, founder of the Sierra Club, had proposed in the 1880s when he advocated for Congress to first establish the park.

The property is 793 acres, and appraised in 2005 at $2.1 million.

McClintock, who declined a request for an interview, said in an email that he wants the National Park Service to come up with a plan to use the land because he doesn’t trust the agency after its attempt to ban bicycle rentals and limit other recreation in Yosemite Valley last year. After public outcry, the Park Service rewrote the plan, dropping the controversial limits.

“There is considerable resistance in the House and in my district to the acquisition of additional federal land without clear assurances that it will be properly managed and that public access and recreation will be guaranteed,” McClintock said.

McClintock’s 4th Congressional District, which he has represented since 2009, runs from Lake Tahoe to Kings Canyon National Park, and includes Yosemite.

McClintock also is one of a number of conservative Western Republicans who opposes nearly every effort to expand federal land holdings in the West, preferring it be held in private ownership for cattle ranching, logging, mining and other uses.

“When is enough enough?” he said in a speech on the House floor in 2009. “The public good is not served by the mindless and endless acquisition of property at the expense of the sustainable use of our natural resources, responsible stewardship of our public lands, and the freedom and property rights of our citizens.”

The issue may play a role in McClintock’s re-election.

He is being challenged by Republican Art Moore, a combat veteran and major in the Army National Guard, who said he is in favor of the proposal to expand Yosemite’s boundaries.

“Broad support exists because these bills represent a common sense approach to federal land management and acquisition,” he said in an email. “Rather than the federal government dictating what it will do, this is a situation of willing sellers and government acquisition based on fair market price.”

The process in Congress is fairly straightforward.

Last year, Rep. Jim Costa, D-Fresno, introduced a bill to expand Yosemite’s boundaries by 1,575 acres. The bill, HR1677, would include the 793 acres owned by the Pacific Forest Trust, and another 782 acres of forested land owned by several doctors, who support the legislation.

If approved, it would allow the National Park Service to appraise the properties and buy them using existing money from the Land and Water Conservation Fund, a pot of money funded by royalties on offshore oil drilling.

Sen. Dianne Feinstein, D-Calif., has introduced a bill in the Senate to expand the park boundary. A vote is expected this summer. But if McClintock doesn’t support the measure, the GOP House leadership is unlikely to act, since the land is in his district.

The deal would become Yosemite’s largest acquisition since 1939, when the federal government bought 7,200 acres near Wawona known as the Carl Inn tract from a timber company.

McClintock left the door open somewhat, however, in his email to this newspaper.

“Unless the Senate acts, I don’t foresee action in the House,” he said.

Yosemite officials say they want the land, although they said they can’t formally plan for its future until the government owns it.

“It’s beautiful and there are great views,” said Yosemite spokesman Scott Gediman. “It includes prime habitat for rare species, and it would provide an area for us to potentially develop campgrounds and trails. Any opportunity to expand the boundary of the park is beneficial for everybody.”

Paul Rogers covers resources and environmental issues. Contact him at 408-920-5045. Follow him at Twitter.com/PaulRogersSJMN.