"It's time we get the insurance industry out of the driver's seat and put families in charge of their health care," State Sen. Irene Aguilar, a physician and Democrat from Denver, told The Denver Post last year as she gathered signatures to get the initiative on the ballot.

The main group behind the initiative, ColoradoCare, touts a number of supporters on its website, including the "Democratic Party of Colorado Platform." But while the platform authored by party activists might include support for single-payer care, many of the state's top Democratic leaders, including Gov. John Hickenlooper, oppose the proposal, saying that it will be too expensive and that the burden of such a dramatic initiative is too much for one state to shoulder.

In the wake of polling showing majority approval for the amendment, a political action committee funded largely by the insurance industry is beginning an aggressive campaign in opposition to the proposition.

To the outrage of some progressives, the group, Coloradans for Coloradans, is being advised by a number of Democratic political consultants, including Global Strategy Group, a firm whose other major client is Priorities USA, the Super PAC backing Clinton's presidential campaign.

"[A] sustained campaign pointing out the many flaws in Amendment 69 is essential, especially in such an unpredictable environment," said a memo from Global Strategy Group about the Colorado campaign that the Intercept obtained in May.

The group's website touts prominent supporters from both major parties.

The opposition

Sean Duffy, a spokesman for Coloradans for Coloradans, says the initiative would deal a devastating blow to both the state's economy and accessibility to health care.

In the first year alone, he says, Amendment 69 would increase taxes by $25 billion, creating a disproportionate burden on small businesses. According to a report done by the U.S. Small Business Administration, half of Colorado's workforce is employed by small businesses.

Duffy says the most significant problem with ColoradoCare, though, is the effect it will have on the quality and access to care. He says beyond the tax increases or the fact that the ballot measure hurts seniors and veterans, according to the group, Amendment 69 doesn't spell out or determine what will be covered under the law.

"We don't know what devices, services, or medicine will be covered," Duffy says. "For providers, they don't know what they'll be paid, and there is no guarantee they will be paid. Doctors can fly and drive. They can leave." 

Many proponents of passing a single-payer system in Colorado have said the state could blaze the trail and others will follow, but Duffy says implementing universal care in one state isn't the right way to go about it.

"There are people who think single payer is a great option for the country, but not one state at a time," he says. "There is no way Colorado is going to bend the cost curve for the country."

He points to Vermont, where Gov. Peter Shumlin passionately advocated for single payer, until the plan went south when the state couldn't foot the bill.

Duffy says Coloradans for Coloradans has been out in full force in an attempt to sway voters come November. They've already held several hundred forums this year in an effort to educate citizens about Amendment 69's impact on the state. Outside of that, he encourages all Coloradans to read the initiative in its entirety.

A campaign finance report from the group in May showed the group had raised $1 million, half of which came from Anthem Inc. Big health care players, including Delta Dental, Cigna and SCL Health, chipped in big bucks as well. 

The campaign spending for and against the initiative will in all likelihood eventually dwarf that $1 million figure as national ideological groups and business interests act to facilitate or prevent what could be a major precedent in U.S. health care.