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The group is also pushing the Frac Act, legislation backed by some House Democrats that would require all energy companies to disclose the chemicals they use during the process. Colorado and some other states have enacted similar legislation, and many natural gas firms voluntarily list their mixtures on the Internet.

Most companies recycle and reuse their water rather than injecting it back into the earth. The reinjection process is blamed for minor earthquakes such as those in Ohio.

The industry has made concerted efforts to become more open and responsible over the years by disclosing the use of chemicals and recycling water, but it has frequently underestimated the passion of its opposition, said Daniel Kish, senior vice president of policy at the Institute for Energy Research.

“To the opponents, this is street theater,” he said. “It’s about doing movies, documentaries, demonstrations, all of which bring attention. They’ll use everything. Earthquakes, water pollution, air pollution, global warming, you name it. Any excuse, anything that will get traction. And [the gas industry] always underestimates the money that the opposition has to spend.”

In response, the industry cites its contributions to the economy. In the first two quarters of last year, 27,000 jobs were created in the Marcellus Shale region, one of the richest gas deposits in the world, according to data from the Pennsylvania Department of Labor & Industry.

Such figures likely will make it difficult for the Obama administration to outlaw the practice entirely. Instead, Mr. Kish and others say, if President Obama wins a second term, the EPA will slowly strangle the process and make it virtually impossible for companies to employ fracking.

“They understand that it’s easier to boil a frog slowly,” he said.