Moving thatOverton window — the spectrum of ideas the public will accept —captures the progressive strategy for making the government'sMedicare program available for everyone. (Photo:Shutterstock)

A clamor to create “Medicare for All” has exploded on the left.Democratic presidential hopefuls are racing to co-sponsor legislation, rising stars in theparty are embracing it, and national polls show Americans warmingto the concept.

But even the idea's most fervent backers acknowledge that thegoal is far off in the distance, beyond the next yearor even the 2020 election.

Related: Single-payer vs. Medicare for All: What's thedifference?

Their aim for now is to shift the health care debate. By making single-payerhealth care — a model under which all Americans would get theirinsurance from a single government plan — the progressive position,advocates argue that gives Democrats representing conservativeareas of the country political cover to support more modestproposals to expand the government's role in health insurance.

“Everybody understands we're not going to get Medicare for Allenacted in January. But it's a marker about where we want to land,which is to say we want everybody to have health care,” DemocraticSenator Brian Schatz of Hawaii said in an interview. “This is aboutmoving the so-called Overton window.”

Moving that Overton window — the spectrum of ideas the publicwill accept — captures the progressive strategy for making thegovernment's Medicare program available for everyone, not justthose over 65. Schatz, for instance, is a co-sponsor of SenatorBernie Sanders' Medicare for All legislation, but has also offereda less comprehensive alternative which would give states theauthority to let people who aren't otherwise eligible buy into theMedicaid program targeted to aiding low-income individuals.

Obamacare challenge

The maneuvering on health policy comes as the Affordable CareAct, which expanded insurance coverage to millions of Americans, isunder a Republican-led court challenge. While the law, popularlyknown as Obamacare, remains in effect, the court case may drag intothe 2020 campaigns for the White House and Congress. In themeantime, there's a wide range of potential proposals between thestatus quo and a government-run single-payer system that aregaining support among Democrats.

“We will be having a conversation about many ideas on how we canlower the costs of health care,” said Representative Ben Ray Lujánof New Mexico. The Democratic-led House will discuss the Medicaidbuy-in that he co-sponsored with Schatz, as well as Medicare forAll and “other initiatives members have, as opposed to Republicanswho were only intent on repealing the Affordable Care Act,” hesaid.

Republican opposition

President Donald Trump and his fellow Republicans are unlikelyto give up their opposition to Obamacare, much less embrace anexpansion of Medicare. Any hope of movement would rely on Democratsriding the issue to control of the White House and both chambers ofCongress in 2020.

Senate Minority Leader Chuck Schumer declined to say if hesupports Medicare for All. “There are lots of different routes,”the New York Democrat said on NBC's “Meet The Press” program onDec. 16. “Many are for Medicare for All. Some are for Medicarebuy-in. Some are Medicare over 55. Some are Medicaid buy-in. Someare public option.”

Schumer said Washington has to “do a lot more on health care,”and that it'll be “a major issue in 2020.” Representative NancyPelosi, poised to become House Speaker in January, has also kepther distance from a federal single-payer program, suggesting statesadopt it first.

Political attacks

While Republicans have struggled to coalesce around a healthcare alternative, they found unity in attacking Medicare for Allagainst Democrats in 2018 House races, calling it a radical andcostly government takeover of health care. Democratic candidatesrunning in swing districts generally distanced themselves from theidea.

But the Kaiser Family Foundation found in March that 59 percentof Americans favor “Medicare for All,” a figure that's grown inrecent years, while 38 percent oppose it. Support fell to 53percent, though, when it was dubbed a “single-payer plan.”Meanwhile, 72 percent favor a “Medicaid buy-in for everyone” and 75percent favor an optional “Medicare for All” proposal that alsolets people who already have coverage keep their plans.

The obstacles are enormous. Major changes to health care arepolitically treacherous as Americans, about half of whom getinsurance from an employer, fear their coverage will be reduced.Opposition from industry and conservatives would make plenty ofDemocrats wary of such a disruptive change.

Practical strategy

“We don't have the support that we need,” said RepresentativePramila Jayapal of Washington, who will co-chair the ProgressiveCaucus. She said that she'd favor modest expansions of Medicare orMedicaid eligibility as a step toward Medicare for All.

“I am a big bold thinker; I'm also a good practical strategist,”Jayapal said. “It's why the Medicare For All Caucus was started,because we want to get information to our members so people feelcomfortable talking about the attacks we know are going tocome.”

The Democratic Party shift is already under way. In September,former President Barack Obama praised Democrats are running on“good new ideas, like Medicare for All” — a stark reversal after herejected the idea of a single-payer system at the outset of hishealth care overhaul push in 2009. Medicare for All legislationoffered by Sanders is backed by numerous Democratic senatorsconsidering 2020 presidential bids, including New Jersey's CoryBooker, New York's Kirsten Gillibrand, California's Kamala Harris,and Elizabeth Warren of Massachusetts.

Top issue

The Sanders proposal is estimated to raise federal spending by$32 trillion, according to a study by the conservative MercatusCenter, which also found that it would modestly reduce overall U.S.spending on health care by saving money on provider payments andadministrative costs. In other words, Americans would pay highertaxes to finance universal coverage and save on premiums andout-of-pocket costs.

“Our first job is to defend the Affordable Care Act. Our secondis to improve it and make changes, for example to families'vulnerability to the impact of high-priced drugs. And the third isto find a system of Medicare available to all that will increasethe qualify of care while it decreases the cost of all of us,”Warren said in an interview.

Jayapal predicted it would be “the top issue of the 2020presidential campaigns.”

“The left is not bulls—ing when it suggests we should have asingle-payer system, but there is definitely some Overton windowplaying on Medicare for All,” said Sean McElwee, a left-wingactivist and researcher with advocacy group Data For Progress.

'Political hurdles'

McElwee said there are “significant political hurdles in the wayof single payer” and there likely will be attempts “water down” theidea of Medicare for All so that it becomes palatable to centristDemocrats.

The biggest challenges, he said, will be in the Senate, whereless populous, solidly Republican states are on equal footing withlarger, solidly Democratic states and there's a 60-vote thresholdfor legislation. In addition, several Democratic senators,including Ohio's Sherrod Brown and West Virginia's Joe Manchin,have conservative constituencies.

Even before the next Congress convenes in January, young,newly-elected House progressives like Alexandria Ocasio-Cortez ofNew York and Ilhan Omar of Minnesota are pushing the idea ofMedicare for All to their social media followers. Liberal groupslike MoveOn and the Sanders-aligned Our Revolution want to make ita litmus test for Democratic presidential candidates in 2020.

“In the debate about what it means to be a Democrat, theprogressive vision has won out. They've lost the war. They're goingextinct,” McElwee said of some of the conservatives who prevented asingle-payer system from being considered when Obamacare was firstdebated. “They're like the dinosaurs and the meteor's alreadycoming.”

Read more: 

• Trump goes after Medicare for All–and gets it allwrong
• Medicare For All: The discussion heatsup
• Next up for GOP: Shooting down Medicare forAll

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