Here in the self-proclaimed "Cowboy State" -- the home state of Interior Secretary James G. Watt, a land awash in oil money and bursting with boom towns -- an unlikely coalition is rushing to defend a six-mile stretch of virgin woodlands against the bulldozers and drills of a major oil company.

Grizzly bears have long outnumbered avowed environmentalists in Wyoming, an atmosphere that Watt often credits with inspiring his pro-development creed. But it is also here that Watt faces one of his most determined challenges. And the target is an energy development project.

The rescue posse began saddling up when the Reagan administration gave Getty Oil Co. the go-ahead to plow a road in the shadow of the Grand Tetons and drill for what is believed to be a wealth of natural gas.

Its ranks include Wyoming Gov. Ed Herschler -- a folksy and headstrong Democrat often known as "Governor Ed" -- who has never before challenged a federally approved drilling project. Also on board are such normally disparate forces as hunters and fishermen, businessmen and ranchers and a bipartisan mix of Jackson Hole politicians.

While there are key omissions from the ranks, including the Jackson area Chamber of Commerce and Wyoming's all-Republican congressional delegation, the significance of this uprising has been lost on no one.

"For someone who was born in this state, this is fascinating," said Sen. Alan K. Simpson (R-Wyo.), a former state legislator who helped lead a popular campaign in the 1970s banning additions to Wyoming's wilderness system. "Ten years ago, there was a very clear feeling that we had enough wilderness in Wyoming. We'd coughed up the largest number of acres of any state except Alaska. Now it's obvious to me from reading my mail that people want more of it."

At issue, according to the protesters, is not just one gas well, but a way of life. The unspoiled outdoors has always been regarded as a bounteous resource here, a feeling reflected in this thumbnail sketch from the state travel commission: "Wyoming is an experience . . . a place where you can see for a hundred miles, taste the sweet water of a mountain stream, feel western history in its most recent setting . . . . Wyoming is What America Was."

This feeling endured the boom of the last decade that transformed Wyoming from a predominantly agricultural state into one whose No. 1 industry is energy development. The anxiety now is partly in response to the march of oil and gas development beyond the boom towns into relatively unexplored woodlands like those around Jackson.

But state officials said in recent interviews that the threat also comes from Washington, where the Reagan administration and native son Watt have introduced a pro-development thrust into the management of federally owned lands, which cover about half of Wyoming.

"We felt the previous administration was overly restrictive and we let them know it," said Herschler. "Now we've got an administration that's freer and we have to turn to protecting our own environment. We're forced to take positions we didn't have to take before."

Rep. Dick Cheney (R-Wyo.) said he received 1,000 letters of protest when the administration announced last year that it was considering oil and gas leasing in the popular Washakie wilderness east of Yellowstone National Park.

Now, in response to Getty's proposed drilling project in Jackson Hole, hunters and fishermen are warning of danger to game herds, businessmen speak of threats to the state's valued tourist trade and politicians are complaining of threats to Wyoming's life style.

"We're still pretty small fry out here," said Herschler, a rancher and lawyer who sports a lapel pin in the shape of a bucking bronco, the state symbol. "We see a multinational corporation and the federal government come in and say they're going to tell us how to run this state. We take the position that Wyoming is not for sale."

"It's not just one well pad, it's not just one road," said State Sen. John Turner, a Jackson Republican who runs a dude ranch and an outfitting business dependent on heavy tourist traffic. "It's the question of what happens after they find something? What if this whole area gets busted open for several decades? Then what do we have left?"

If the stakes seem high for Wyoming and Jackson, they are equally so for Getty and, by extension, for other companies interested in exploring sensitive environmental areas.

At the heart of this controversy is a hump in the earth, a structure more than a million years old, located on a mountaintop about 13 miles southeast of Jackson. Getty geologists say they believe that it holds about 300 billion cubic feet of natural gas, worth about $1 billion on today's market.

Dick Hamilton, Getty's manager for exploration and production in the energy-rich Rocky Mountain states, rates the Jackson Hole hump, known as an anticline, as the company's hottest current prospect in his area. Getty has spent more than $1.2 million on studies of the structure and on legal fees, and plans to spend $14.7 million more to drill the first well, Hamilton said.

"It would definitely set a bad precedent if it were ultimately decided we couldn't drill here," Hamilton said. "We have the lease. We have the permits. If it were stopped now, it seems very unlikely that a permit would be issued in a comparable situation."

Even many opponents of the Getty project concede that the company has a strong legal claim to proceed. Getty obtained a lease to explore the area several years ago, in an era of less vigilance about prospective energy development in the Jackson region. But by the time Getty applied for federal permits to begin drilling the political climate had changed.

By then, the Carter administration and the state had recommended that the area where Getty plans to drill -- the Gros Ventre (big belly, in English) region of the Bridger-Teton National Forest -- be protected as a wilderness area.

The House of Representatives recently voted to place an immediate ban on future oil and gas leasing in such regions, and more than half of the Senate has sponsored a similar measure. Forest supervisor Reid Jackson said in an interview that the government probably would deny Getty a lease here if the company applied for one today.

But the Interior Department and the Forest Service have taken the position that it would be illegal to deny Getty the right to use its pre-existing lease. In May, they issued Getty the needed permits to drill, concluding in an environmental impact statement that the wilderness qualities of the area could be restored after development.

"Every precaution will be taken to mitigate impacts," Interior Undersecretary Donald P. Hodel wrote to Herschler last month.

The Wyoming congressional delegation essentially has sided with the administration, sponsoring a bill that would exclude the leased section of the Gros Ventre woodlands from the state's wilderness system. The measure has not come up for a vote.

Opponents contend that the government has the right to block the project because of the fragile quality of the Gros Ventre woods. They argue that the unstable soil and steep slopes would be impossible to restore after development.

The woods now provide grazing for elk, wintering range for moose and summer habitat for bighorn sheep. Little Granite Creek, which flows along Getty's proposed road route, is home to Wyoming's only indigenous fish, the cutthroat trout.

"If you can't stop them here," said Sierra Club national board member Phil Hocker, a Jackson architect, "you can't stop them anywhere."

The go-ahead from Washington appeared at first to leave the protesters little recourse. The federal government is the sole landlord of the Jackson Hole hump, owner of both the land above it (through the Forest Service) and the minerals beneath it (through the Interior Department).

That situation changed this summer when Herschler and his aides unearthed an obscure state regulation that appears to give Wyoming a veto over drilling projects that could cause "unreasonable surface damage" -- whether on federal, state or private land.

The state had never before held up a federal drilling project, and many Wyoming officials said they did not even know the commission had such powers.

But in June, the Wyoming Oil and Gas Conservation Commission convened hearings on the Getty well, forcing a delay in the project pending further study of its environmental impacts.

In Jackson, the drama has been recast as a showdown between "the people" and big business. This is partly due to the entrance on the scene of flamboyant Jackson attorney Gerry Spence, nationally known for defending the little man against big corporations -- the Karen Silkwood case against Kerr-McGee, the $26.5 million libel suit by former Miss Wyoming Karen Pring against Penthouse magazine.

"We're going to drive the snakes out of the Garden of Eden," said Spence, who recently announced that he would represent the local protesters free in administrative appeals or in court.

Getty officials, at first taken aback by the uproar, have since sought to calm fears and present themselves as good neighbors. Getty joined the Jackson Hole Area Chamber of Commerce and bought six tickets to the Chamber's annual dinner. It has conducted guided tours for local officials and citizens to the reclaimed site of a nearby Getty well and has spread the word that the project would return hefty revenues to Teton County and the state. The Chamber's board of directors voted earlier this year not to oppose the drilling project.

"I tell people that the worst thing we could do is go into that area and not do a responsible job of caring for the environment," said Robert Jacobs, Getty's regional public affairs manager in Denver, who shuttles regularly between there and Jackson. "We'd like to drill again in that county and we'd never get to if we did a poor job."

For now, the project is stalled, awaiting a ruling by the state Oil and Gas Commission. If the delay lasts past mid-September, Getty's Hamilton said, the cold weather will force the oil company to shelve the project until next year. By then the case is likely to be in court, according to parties on all sides.

Federal officials, sensitive to the states' rights issue, have said they are not sure whether Getty should proceed on the strength of the federal permits alone. "It's somewhat of a question," was all that an Interior Department official would say.

Herschler has suggested that Congress exchange Getty's Jackson Hole lease for other lands in less sensitive areas, since Wyoming has more than 4.6 trillion cubic feet of untapped natural gas, according to a 1980 state study. But the Wyoming delegation and federal officials have said it would be difficult to strike such a deal since no one knows the real value of the Getty lease.

"Don't get me wrong, I'm not a wilderness nut," the governor said. "But this area has all the characteristics of a wilderness area, and until Congress decides on it one way or the other, I just think we ought to leave it alone. Wyoming is providing a pretty fair share of this country's energy needs. We welcome industry here. But we want them here on our terms."