EATTLE, May 14 — Western Republicans and property-rights groups, after years of fighting environmentalists over restrictions on land use, are gearing up to oppose the Bush administration on an issue at the heart of regional fears about overreaching federal power.

President Bush's energy plan, set to be released on Thursday, is widely expected to include recommendations to allow the federal government to seize private property, using eminent-domain authority to place new electric transmission lines, administration officials say.

But any plan to expand the federal government's ability to condemn private property is likely to run into heavy opposition in a region that has long been staunchly Republican.

"Private property is sacred property," said Sarah Berk, a spokeswoman for Senator Larry E. Craig, Republican of Idaho, who was instrumental in stripping out a federal eminent-domain provision from a Senate energy bill earlier this year. "Senator Craig definitely feels this issue is best left up to the states."

In recent days, Vice President Dick Cheney has spoken of the need to give the federal government authority to condemn private property to ease the way for thousands of miles of new power lines — something that would require the approval of Congress.

This authority is now granted for placing natural gas lines, but not for expanding the electric grid.

Mr. Cheney has not said how hard the administration will push the idea. But Western governors have been told by federal authorities that the electric grid needs to be expanded by as much as 55,000 miles, and that this cannot be accomplished without granting the Federal Energy Regulatory Commission new powers to condemn property.

"If it's going to be anything like the trouble we've had siting natural gas pipelines, I'm worried — based on all the complaints we've received," said Chuck Cushman, executive director of American Land Rights, a property-rights group in Battle Ground, Wash. "It's a dangerous business giving power of condemnation to any federal agency."

His group has spent years fighting federal agencies like the National Park Service, and the Forest Service about everything from park expansion to endangered species. Those fights — which are usually about restrictions on private land and do not always involve eminent domain — could pale when compared with disputes over condemning property for a huge expansion of power lines.

Several Western governors, among them Michael O. Leavitt of Utah and Dirk Kempthorne of Idaho — both Republicans — have already cautioned the Bush administration against any new federal eminent- domain authority.

The governors say there is a need to build new transmission lines and towers to satisfy soaring energy demands. But they are leery of giving condemnation powers to the federal government — a right the states now use to place their own power lines.

"That's the kind of solution that gets everyone nervous and brings out the antifederalist in a lot of people," Governor Leavitt said last week.

Though most of the West has long been reliably Republican, and has opposed many initiatives to restrict property for environmental reasons, government plans to expand freeways, military installations or nuclear waste sites have scrambled traditional political positions.

Eminent domain — in which the government condemns a private property, establishes a fair-market value for it, then pays the property owner that price — is usually evoked for highways or military facilities.

In Utah, Governor Leavitt faces widespread opposition to his plan to build a new 120-mile road parallel to Interstate 15 through Northern Utah, called the Legacy Highway, from an unusual alliance of environmental, farming and community groups. The groups have cited private property concerns among their reasons for opposing the freeway.

In Idaho, Governor Kempthorne, like Senator Craig, said he believed eminent-domain authority for electrical transmission lines should be left to the states. Mr. Cheney has complained that the tangle of different state jurisdictions has made it difficult to plan and locate power lines that unite entire regions.

Not all property-rights groups are opposed to enhanced federal authority. Nanci Marzulla, who heads Defenders of Property Rights, a group in Washington, D.C., which has filed many legal challenges to environmental property claims, said her organization did not object.

"It's a breath of fresh air having an administration that wants to buy private property instead of just take it," said Ms. Marzulla, who advised the Bush transition team on environmental matters. She was referring to restrictions on private property, which some critics say amount to an outright taking of private property without compensation.

"The power of eminent domain is the inherent power of the sovereign," she said. "This is something we took from King George. And the only restrictions our founders put on it are that the property be for public use and that the property owner be justly compensated."

Ms. Marzulla added, "We will be watching to make sure certain things are put in place to protect land owners, but it sounds like something that will not give us heartburn."

But if the experience of other areas now fighting new power-line plans are any indication, more than heartburn could be ahead.

In California, even with rolling blackouts and daily alarms about the insufficient power grid, a utility's plan to build a $270 million voltage line through 31 miles of parks, farms, wilderness and neighborhoods in Riverside County, has sparked noisy opposition and legal threats.

State energy officials say they always expect opposition from neighborhood groups to new power lines. But given that California is in a power crisis, they are surprised at the depth and fervor of the opposition.

Opponents of the expansion plan say that crackling, overhead lines strung to towers as tall as 19 stories, would ruin a community of rolling hills, vineyards and homes that hark back to a more pastoral California.

"We need to stop this train now before it gets out of control," said Loma Bosinger, a leader in the group fighting expanded power lines. "There has to be an absolute need before you march in and take the home of a United States citizen.

"This is not wartime," she said. "This is about greed and expanding profits of energy companies."