When Clinton gave a speech in October lauding the nation’s oil and gas boom, she was condemned by New Yorkers Against Fracking for her “backward, 20th-century belief” that fossil fuel extraction is good for America. In Colorado, Democratic governor John Hickenlooper supports fracking but has tried to contain a growing local backlash with robust regulation of natural-gas drilling. His reward: Voters in four towns rebelled this fall, passing bans or moratoriums. Colorado is now in the awkward position of suing a fifth town, Longmont, which passed the state’s first ban last year, in order to protect the state’s legal authority. Its litigation partner: the oil and gas industry.

The rebellion across Colorado’s heavily populated Front Range could incite a ballot initiative calling for a statewide ban. “It’s a shot across the bow of state legislatures,” warns Andrew Kear, a geologist and political scientist studying the movement at Ohio’s Bowling Green State University. “The states can’t ignore their municipalities for too long.”

The antifracking movement has gained exceptional strength in Colorado, says Kear, because of an unconventional coalition of environmentalists raising alarms about polluted drinking water, ranchers opposed to drilling on their land, hunters who don’t want wildlife disrupted, and nervous citizens demanding to know what’s in all those fluids being injected into the earth.

Environmental concerns — particularly the potential for groundwater contamination — are fueling the antifracking movement nationally, despite industry efforts to demonstrate that the process is safe. But in Colorado there’s also a not-in-my-backyard factor: Fracking has given rise to industrial developments tucked beside homes and schools and family farms. No one wants his family’s neighborhood to be “fracked.”

Most governors have embraced the revolutionary potential of hydraulic fracturing, which deploys pressurized water, sand, and chemicals to extract hard-to-reach supplies of oil and natural gas. They like the sound of fracking: 1.7 million jobs and rising, billions in revenue flowing into state coffers, revived manufacturing sectors, and, of course, cheaper and (in the case of natural gas) cleaner sources of energy. Governors who are on the fence about fracking, like New York’s Andrew Cuomo, who keeps ordering more studies on the practice, face the wrath of the left and the right alike. The state’s GOP accuses Cuomo of leaving money on the table — letting political calculations get in the way of an economic rebound — while environmentalists call for a ban on fracking.

Other Democrats feeling the heat of a smoldering antifracking movement include President Obama, whose EPA is under attack for failing to hew to activist doctrine that fracking poses a danger to public health and safety. Activists charge the agency with censoring studies purportedly proving groundwater contamination in a Pennsylvania town. (The EPA, which previously concluded the methane contamination was naturally occurring, says a whistleblower’s report is not corroborated.)

As a nation, we already know all about fracking’s vast economic potential. Energy expert Daniel Yergin, vice chair of IHS, recently credited fracking with “improving the competitive position of the United States in the global economy, and beginning to affect global geopolitics” as U.S. dependence on Middle East supplies plummets.

The big unknown is domestic politics. Industry leaders mostly dismissed last fall’s Colorado votes as symbolic. That sounds like wishful — and shortsighted — thinking. Signs of public alarm will be picked up and broadcast by nervous politicians. Starting with the 2016 Democratic presidential candidates.

This story is from the December 23, 2013 issue of Fortune.