Coming off fresh victories in three Colorado cities — and nearly a fourth — anti-hydraulic fracturing activists in the Rocky Mountain State are looking toward a potential statewide referendum on whether to ban the drilling method.

"Everything is on the table," said Sam Schabacker, Mountain West region director with Food and Water Watch.

Food and Water Watch helped campaign in support of ballot measures to either permanently or temporarily ban fracking in Boulder, Fort Collins, Lafayette and Broomfield, the latter of which failed narrowly.

Rep. Cory Gardner, R-Colo., who represents an eastern swath of the state that includes the Niobrara Shale play, is wary of the mounting municipal initiatives.

"It's all leading, I believe, to a November 2014 ballot initiative to ban hydraulic fracturing statewide. If Colorado does that, that same initiative will spread around the country to other states ... and cripple our ability to be truly North American-energy secure," he said at a recent Washington event.

Fracking injects a high-pressure cocktail of water, sand and chemicals into tight rock formations to tap hard-to-reach hydrocarbons buried deep underground.

The practice has invited concern from public health and environmental groups about its impact on drinking water, leading to a rash of local efforts in Colorado, Ohio, New York and other states to either suspend or block fracking.

But the oil and gas industry contends fracking, which has led to a domestic energy boom, is safe.

The Colorado Oil and Gas Association, which opposed the ballot measures, painted the successful initiatives as outliers.

Boulder and Fort Collins are college towns — and of Lafayette, Schabacker said that "there's no denying it's Democratic-leaning."

Therefore, Broomfield is the more instructive example of Colorado voters' tastes, said Tisha Schuller, COGA's chief executive.

"The close election in Broomfield proves that common sense prevails in mainstream Colorado communities when it comes to energy production," she said.

But Schabacker shot back that even conservative-leaning cities in Colorado have rejected fracking. He pointed to last year's ballot measure to ban fracking in Longmont, a predominantly white and conservative city northwest of Denver.

"If I were the industry, I would be really, really scared," he said.

Local organizers are emboldened and are quick to note they were outspent by COGA in each city.

By Schabacker's count, proponents of the measures chipped in $26,000 across the state. COGA spent slightly less than $900,000 attempting to defeat them, according to the Denver Post.

Still, some towns and cities across the country are exercising caution because of potential lawsuits from the oil and gas industry, said Kate Sinding, senior attorney with the Natural Resources Defense Council.

She mentioned Longmont, which is facing a lawsuit that includes Democratic Gov. John Hickenlooper as a plaintiff.

"There is understandably some conservativeness on the part of getting themselves too out in front on this issue, and it really argues for some clarity on the state level," she said.

Still, Sinding said that the public will and city governments are aligned in many of the ballot initiatives across the country.

"There is a pretty strong trend now over at least the last two elections in Colorado that localities in that state feel very strongly about fracking," Sinding said. "It's a similar trend to what we're seeing play out in many other states."

Schuller noted that anti-fracking activists are likely to continue pushing ahead.

"This election represents round one with many more to come," she said.

The oil and gas industry is backing a new group aimed at convincing Colorado voters that fracking is safe and that the regulatory framework brokered by Hickenlooper, industry officials and environmental groups would keep the practice in check.

"In Colorado especially, there are high standards and model regulations in place to ensure that the health and safety of our communities come first. As we discovered in Tuesday's election, many don't know that," said Jon Haubert, spokesman with Coloradans for Responsible Energy Development, which is financed by Anadarko Petroleum and Noble Energy.