The rule, which was finalized under President Barack Obama in November, would require oil and gas companies to actively plug leaks of natural gas while scaling back their practice of intentionally venting or burning the gas in order to extract more profitable crude oil.
The drilling industry, however, supported Republicans' efforts to overturn the rule, saying it would undo the costly regulation, which is viewed as a threat to jobs and operations.
As the clock ticked down toward the final hours that the Senate could use the Congressional Review Act with a simple majority -- the deadline is Thursday -- Republicans failed in a procedural vote to turn back the Bureau of Land Management regulation.
In the end, three Republicans crossed the aisle to side with Democrats, handing Senate Majority Leader Mitch McConnell a rare legislative defeat by just one vote, 49-51.
Vice President Mike Pence was there to break a potential tie, but he ultimately wasn't needed.
Democrats united against the measure and were joined by Republican Sens. Lindsey Graham of South Carolina, Susan Collins of Maine and John McCain of Arizona. Graham and Collins had publicly opposed the repeal, but McCain was a surprise "no" vote.
Graham told The Hill
earlier that a CRA resolution on the rule would be "substantially the same" as the one overturned, adding that he preferred a full replacement of the regulation.
"I think we can replace it with a better reg, rather than a CRA," he said.
Despite the loss, leaders at the Department of the Interior plan to suspend or revise the methane rule through a rewrite process.
"As part of President Trump's America-First Energy Strategy and executive order, the Department has reviewed and flagged the Waste Prevention rule as one we will suspend, revise and rescind given its significant regulatory burden that encumbers American energy production, economic growth and job creation," Kate MacGregor, acting Assistant Secretary of the Interior for Land and Minerals, said in a statement
Environmental groups were primed for the short victory after seeing a number
of other departmental regulations overturned or delayed since Trump became President. At least one group also views the Department of the Interior's promise to re-open the rule-making process as a good sign.
"The next step is there will be a rule-making process to entertain changes to the rule, so that should be based on evidence, stakeholder input and public comment. In that sense, that is a much more reasonable process to the CRA," said Jeremy Martin, a senior scientist at the Union of Concerned Scientists. "Clearly the instinct of the administration is to weaken and undermine these kinds of protections. I don't think that makes sense at all, but at least this process will give us the opportunity to submit evidence."