Senate staffers were optimistic last week the sprawling energy bill from Republican Lisa Murkowski and Democrat Joe Manchin III could move fast. With the measure zooming past the Senate Energy and Natural Resources Committee, they expected it could get a quick floor vote, then wing its way to the House.

But as the Senate took up the bill Wednesday and senators offered dozens of amendments, the measure was dragged in myriad directions and its path grew muddled.

And prospects for the bill’s quick passage only dimmed late Wednesday after Sen. John Kennedy, a Louisiana Republican, threatened to object to every amendment until the Senate votes on his bipartisan, industry-supported measure to reduce the emission of highly potent greenhouse gases called HFCs, for hydrorflourocarbons. Such a move would delay the package and could upend it entirely.

Kennedy told reporters he didn’t have any other option but to object to all proposed amendments. He and Sen. Thomas R. Carper, Democrat of Delaware, spoke on the chamber floor about their bill, urging a roll call vote on it. A similar House bill has bipartisan support, too. A version of the legislation is among the energy bill’s proposed amendments.

Many of those proposed amendments are ambitious, including provisions to extend an offshore oil-drilling moratorium in Florida, cap tax credits for electric vehicle buyers, extend renewable energy incentives, revive an Obama-era methane regulation, raise royalty fees on mining companies and halt any changes the White House is pursuing to the National Environmental Policy Act, a 1970s bedrock federal law.

“I know folks are looking at [this bill] for the first time, as they’re not on the committee, and they have ideas that are good and worthy,” Murkowski, an Alaska Republican, said Wednesday morning. “I want to have votes. The leader has said that he wants to have this open amendment process,” she said of Majority Leader Mitch McConnell.

Murkowski said more than 150 amendments to the bill had been submitted by Wednesday morning, adding that she was working on a managers’ package — a group of amendments to be voted on in a block — of “noncontroversial” measures.

“I want to have a managers’ package, but it is entirely possible — we’ve seen it before — that that opportunity is spoiled,” she said.

As drafted, the bill would address energy efficiency, battery storage, carbon capture technologies, nuclear energy, the power grid, critical minerals and a host of technical energy hurdles.

Sens. Tom Udall, a New Mexico Democrat, and Charles E. Grassley, an Iowa Republican, attached an amendment to raise the royalty fees energy and mineral extraction companies would pay on federal lands from 12.5 percent to 18.75 percent.

‘Sweetheart deal’

“The current regulatory system allows companies to get a sweetheart deal on federal public lands,” Grassley said. The provision was a much-needed update to federal mining laws more than a century old, he said. “It is time — hence our amendment — for my colleagues in Congress to end this oil company loophole and bring oil leasing into the 21st century.”

Udall offered a separate amendment to restore a federal regulation, which the Bureau of Land Management wrote during the Obama administration, to limit methane emissions.

The EPA rolled back a different methane rule in August, despite criticism from environmentalists and the oil and gas industry.

Exxon Mobil Corp., which supported the rule, unveiled a proposal Tuesday to cut methane emissions. “Our industry has developed high-tech advances to curb emissions, and we also hope this framework will be helpful for governments as they develop new regulations,” Darren Woods, the Exxon Mobil chief executive, said in a statement.

Bipartisan support

Limiting HFCs — substances found in refrigerants, insulation, fire fighting foam and other materials — has broad bipartisan support in the Senate and the backing of environmental groups and the chemical industry, which has replacement chemicals ready for deployment.

The U.S. could also slash emissions from HFCs, which are thousands of times more powerful greenhouse gases than carbon dioxide, if the Senate ratified the Kigali amendment to the Montreal Protocol, an international deal reached in 2016 in the Rwandan capital. The administration must submit paperwork to the Senate for that to happen but it has not done so.

Clearly frustrated, Kennedy cast doubt on the broader energy bill’s chance at becoming law.

“I’m planning on voting against the bill. I don’t think it has a hope in hell in passing the House anyway,” he said, adding that bundling in the HFC bill could sweeten passage in the House.

“I don’t think Speaker Pelosi’s going to agree to this.”

Earlier, Sen. Sheldon Whitehouse, a Democrat of Rhode Island, said three additions — the HFC provision, an energy efficiency bill offered as an amendment by Sens. Jeanne Shaheen, a New Hampshire Democrat, and Rob Portman, an Ohio Republican, and an amendment to extend tax incentives for low-carbon energy — would round out the bill nicely.

“We add those three things to it, all of which are bipartisan, and all of those are positive consequential steps,” Whitehouse told reporters. “We got a pretty darn good bill.”

He said Tuesday night he was not aware of an agreement on amendment procedure.

“We don’t have the agreement yet, but I would hope that there’d be a number of amendments that get voted on.” Whitehouse said. “And I would hope that there are a whole bunch of more amendments that get allowed in the manager’s package that are not particularly controversial.”

On Tuesday, Florida GOP Sens. Rick Scott and Marco Rubio filed an amendment to extend the offshore oil-drilling moratorium in the eastern Gulf of Mexico until 2032. The moratorium expires in 2022.

As the Senate process unfurls, Indiana Republican Mike Braun and Oregon Democrat Ron Wyden may be on a collision course over tax credits for electric vehicles.

Along with pushing for the extension of the production and investment tax credits, as well as the residential energy and energy efficiency tax credits in the package, Wyden is trying to tack an EV tax credit to the bill.

“Right now, taxpayers can receive tax credits for the purchase of a new electric vehicle or fuel cell vehicle,” a summary of the proposal says. “The Wyden Amendment,” it says in part, “would expand the per-manufacturer limitation for electric vehicles to 600,000 and extend the credit for fuel cell vehicles through December 31, 2024.”

Braun filed two amendments to limit those credits. One could halt credits for vehicles more expensive than $45,000. The other would prevent credits from applying to taxpayers with annual incomes of more than $163,000.

Another amendment, from Washington Democrat Maria Cantwell, would halt the White House Council on Environmental Quality from changing the National Environmental Policy Act, a robust law that mandates environmental assessments on energy projects.

The Trump administration announced a rollback of NEPA in early January.