Loveland, Colo., has been best known nationally for its romantic name; each February, more than 100,000 letter-writers send notes through the city to their sweethearts. Loveland relies on volunteers to hand-stamp the mail with a love poem and forward the letters on to their intended valentines.

But next week, Loveland might well be the site of an epic break-up between Colorado’s environmentalist liberals and its Democratic establishment. The city’s 70,000 residents will vote on a highly divisive fracking moratorium, becoming the latest in a series of Front Range communities to weigh restrictions on this technique for extracting underground natural gas and oil.

Floyd Ciruli, a Denver-based independent political consultant, calls Colorado “ground zero for a great hydrocarbon battle in the country.” The Loveland vote, he says, will test whether environmentalists can gain by pursuing strategic local-level restrictions against fracking. But these local votes, paired with proposed state-level ballot-initiative efforts, have created a major fault line among Colorado Democrats.

“The Democratic party is tremendously divided,” Ciruli explains. “That’s the gist of the problem here for the Democrats. Probably the rank and file oppose fracking . . . but the Democratic-party establishment is mostly in favor of it, including the governor, who is strongly in favor of it.”

Since 2012, the towns of Longmont and Lafayette have banned fracking outright, while Boulder, Fort Collins, and Broomfield have all enacted moratoriums. All of these restrictions are facing acrimonious challenges in court from energy companies and from the property owners who collect mineral and land leases.

Representative Jared Polis, a Democratic millionaire who has broadly opposed fracking, has championed about a dozen state-level ballot measures aimed at restricting the process across Colorado.

A November Quinnipiac University poll reported that 51 percent of Colorado residents supported fracking, while 34 percent opposed it. But the fact that support is teetering around 51 percent appears to be making Governor John Hickenlooper, a longtime supporter of natural-gas development, nervous.

Hickenlooper is pushing for a special-session legislative compromise to further regulate fracking; such a compromise would allow more flexibility than a ballot measure. Former governor Roy Romer and former senator Ken Salazar (both Democrats) have also backed the governor’s efforts. Meanwhile, Senator Mark Udall, a Democrat who is facing a tough challenge from Republican representative Cory Gardner, has remained noticeably silent on the issue.

“This is really an internal Democratic-party fight, which I think they’re worried could go into the election and cause the governor and maybe Udall a lot of controversy,” Ciruli says. “They would end up being out of alignment with their base, which is environmentalist.”

The fate of fracking in Colorado — as well as its impact on the state’s Democratic party — will be closely watched nationwide, says Karen Crummy, the communications director for Protect Colorado, a group backed by the energy sector.

“Colorado has been often mentioned in the last decade as being a purple state,” Crummy says. “We also have relatively loose ballot rules. So groups tend to come in here and test-drive initiatives. I think the marijuana measure that passed last year is a perfect example.”

If such localized efforts succeed in Colorado, expect them to be replicated elsewhere, says Stan Dempsey, president of the Colorado Petroleum Association.

“Nationally, I think the anti-fracking movement is hoping to ban fracking in Colorado and then move throughout the country to ban it nationwide,” Dempsey says. “The entire effort, whether it be local government regulation or ballot issues or moratoriums or health-impact studies — it’s all about banning natural gas.”

Meanwhile, local as it is, the Loveland vote will remain a crucial bellwether, determining the extent to which outside donors, as well as Colorado’s divided Democrats, will support or disavow natural-gas development.

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— Jillian Kay Melchior is a Thomas L. Rhodes Fellow for the Franklin Center for Government and Public Integrity. She is also a senior fellow at the Independent Women’s Forum.