As the rollout of Obamacare clunks forward, activists who opposed the law from the beginning say it is time to seize the moment, to tear down the current health-care edifice and start anew, especially now as frustration with the law’s implementation is reaching a peak.

These are not Tea Party activists but advocates for a single-payer health-care system who say some of the problems with the launch of the Affordable Care Act—in addition to built-in problems with the law itself—have made the American public more receptive than ever to a Medicare-for-all kind of coverage system.

On Monday, Sen. Bernie Sanders (I-VT) introduced the American Health Security Act, which would require each state to set up a single-payer health-care system and would undo the exchanges that have plagued Obamacare. Meanwhile, various state-led efforts are under way that advocates hope will sweep the country statehouse by statehouse, as soon as lawmakers see the advantage of a single-payer system. In Vermont, for example, lawmakers have set aside the financing and are already preparing to adopt a single-payer system when the federal government permits it, which according to provisions of the Affordable Care Act will be in 2015. In Massachusetts, Don Berwick, a former top Obama administration health official, is basing his campaign for governor on bringing a single-payer system to the commonwealth. And advocates in New York, Maryland, Oregon, and around the country say they see new energy around their cause.

"As the president fully understands, the rollout has been a disaster, the website has been a disaster,” said Sanders in an interview moments after his bill was introduced in the Senate. "But the truth is, even if all of those problems were corrected tomorrow and if the Affordable Care Act did all that it was supposed to do, it would be only a modest step forward to dealing with the dysfunction of the American health-care system. When you have a lot of complications, it is an opportunity for insurance companies and drug companies and medical equipment suppliers to make billions and billions of profits rather than to see our money go into health care and making people well.”

Democrats conceded that Republican efforts to sabotage Obamacare with endless lawsuits and by declining to set up state-run exchanges have damaged the law’s popularity, but they say the confusion will lead the public inevitably to conclude that a simple single-payer system, one that avoids malfunctioning websites and complicated gold/silver/bronze options, is preferable. Advocates pointed enthusiastically to a tweet last month from John Podesta, the former Clinton White House chief of staff who is joining President Obama to help with health care—"Just applied online for Medicare. Took 5 minutes. Single payer anyone?”—calling it proof that wild-eyed radicals are not the only ones supporting single payer. The notion is gradually becoming more mainstream among the Democratic establishment, advocates said.

Republicans "torpedo the Affordable Care Act, and I believe we will now have single payer in this country within the next 15 years,” said Ed Rendell.

"I think the thing that is most interesting about government is that populism gets its biggest support not from Democrats but from what Republicans do,” said former Pennsylvania governor Ed Rendell, who stressed that he did not count himself among the populist members of the Democratic Party. "They torpedo the Affordable Care Act, and I believe we will now have single payer in this country within the next 15 years.”

Opponents to single payer certainly have reasons to believe the momentum is on their side. Further meddling with the American health-care system, after not just the botched rollout of the Affordable Care Act but also the grueling five-year fight to get there, seems unlikely. But proponents of single payer pointed to polls that show a majority of Americans want some version of Medicare for all. It is up to Democratic pols to show leadership on the issue and risk defying the powerful health-care industry, advocates said.

"It is not possible to put together a good program unless you antagonize the powers that be,” said Dr. David Himmelstein, one of the leaders of Physicians for a National Health Program. The White House, he added, "largely played an inside-the-Beltway game in passing Obamacare. They refused to rally the American people for something truly radical which every poll shows that the American people really want.”

Sanders joked that he expected to have his bill passed by chambers of Congress and ready for President Obama’s signature by the time he returns from Nelson Mandela’s funeral in South Africa, but few proponents see much hope of gaining traction for single-payer health care in a Congress that has struggled to pass a routine budget.

Instead they are turning to a legislature-by-legislature fight in statehouses across the country. Advocates in New York and California said they were counting on labor unions’ opposition to the Affordable Care Act—some labor leaders have feared that their members may pay higher premiums under the law and have pushed for exemptions. In Vermont, a single-payer bill passed in 2011, and Dr. Deb Richter, the president of Vermont Health Care for All, said that if anything, the passage of Obamcare slowed the group’s work there.

"We had all the momentum going on the single-payer side, and it was really slowed by the Affordable Care Act,” she said. A state measure similar to Obamacare faltered, she added, because it lacked the appropriate enforcement mechanisms. Now, with the law set to take effect in 2015, advocates are working to calm fears among Vermonters who have been scared off by talk of "socialized medicine.”

"We have all of the right ingredients, but there is a lot of room for mischief. You can confuse people, freak them about rationing and all of that stuff,” said Richter. She said she thought Obamacare’s failure to deal with the spiraling cost of health care would lead more and more people to see the logic of single payer.

"I think that eventually most states will recognize this,” she said. "We keep talking about how the health-care system is unsustainable. We haven’t reached that point yet, but when health care starts eating up 25 percent of GDP and you have hospitals failing, they will look for guaranteed financing, and the only way you get there is through a single-payer system. It is not a matter of if but of when.”