The Democratic Party’s recent progression on the issue is emblematic of a broader shift — the U.S. health care system is headed toward a single-payer system. There are three major factors driving this shift.

Less than two years after the Democratic primary, Sanders introduced his Medicare for All Act in September 2017, a modified version of the American Health Security Act. Sixteen Democratic senators co-sponsored the legislation, including four who harbor presidential aspirations. Similar legislation was introduced in the House earlier in 2017, for which a majority of the Democratic caucus pledged support.

In an interview that spring with The New York Times, then-Sen. Hillary Clinton stated she had “never seriously considered a single-payer system.” During the 2016 Democratic presidential primary, Clinton attacked Sen. Bernie Sanders (I-Vt.) for his American Health Security Act of 2013 legislation, which would have effectively converted the U.S. health care system into a single-payer system. That 2013 legislation received no support from his Democratic Senate colleagues.

— Evolution of Democratic support: Most Democratic lawmakers have historically been reluctant to publicly champion single-payer, recognizing the negative reaction many American voters have had to the concept. That reluctance has begun to ebb, as evidenced by the unprecedented support for the Sanders plan.

Furthermore, in February, the Center for American Progress, one of the most influential Democratic think tanks, released its own “Medicare for All” plan. While the plan does not go as far as the Sanders plan, it is far more aggressive than the public option provision of the Affordable Care Act, which Democrats ultimately abandoned in 2010. Finally, three iterations of Medicare “buy-in” bills have been introduced by Democratic senators in the past year.

A majority of Democratic voters now support a single-payer system, and support for the Sanders/CAP plans has and will continue to serve as a litmus test for the Democratic base in primaries, as it already has in some elections this year. Single-payer health care will likely be one of the top issues in the 2020 Democratic presidential primary.

— Shifting public opinion: Polling has historically been complicated on single-payer. Voters often initially back the concept, but support decreases as they hear of increased taxes and potential access to care implications. However, there are a few trends that illustrate an upward shift in public support.

Since 2000, Gallup has asked on multiple occasions whether the federal government should be responsible for ensuring all Americans have access to health care coverage. A majority of respondents have said yes several times, including 56 percent who said yes in November 2017.

In a March 2014 national survey by Pew Research Center, 21 percent of Americans expressed support for a “single national health insurance system run by the government.” The question was asked again by Pew in June 2017, with 33 percent of Americans expressing support for a single-payer system.

While “government-funded health care” is a phrase that has historically carried a negative stigma, a much more positive narrative exists for government health care programs. Medicare and the Children’s Health Insurance Program have enjoyed overwhelming public support since their inception. Perhaps more surprisingly, public opinion of the Medicaid program is also high — a February survey found that 74 percent of Americans have a favorable view of the Medicaid program.

Taken together, the three major government programs cover nearly 40 percent of the U.S. population and account for one-half of U.S. health care spending. The Centers for Medicare and Medicaid Services is the largest agency by spending in the federal government. If independent, the Department of Health and Human Services would rank as the 16th largest economy in the world, ahead of Argentina and Poland and just behind Mexico. The government already runs a large part of U.S. health care; further expansion is not difficult to envision.

— Unsustainable health care costs: The passage of the Affordable Care Act was driven by a high number of uninsured Americans. The next significant policy change in health care will be driven by rising costs. No approach has successfully reversed course on rising health care costs at the national level. Government and industry have both failed to control costs, as the health care industry inches closer to consuming 20 percent of U.S. gross domestic product.

Though the national impact is staggering, the trend of rising health care costs on families and individuals is simply unsustainable. The cost of health care for the average family of four with employer-sponsored health insurance will exceed $28,000 in 2018. Out-of-pocket spending growth has quadrupled wage growth in the past decade. Though cost growth has slowed from the early 2000s, it still far exceeds wage growth, consuming a growing portion of household income. The health care industry is moving toward a breaking point — a point at which enough Americans will move to support trying single-payer.

The conversation around a single-payer-designed system is not lost on Washington, D.C.-based health care groups. Matt Eyles, the new chief executive at America’s Health Insurance Plans, the trade group for health insurers, recently told reporters at Vox that he was “very mindful” of the push toward single-payer. And several prominent health care trade groups are currently working together to conduct research on voter opinions of a single-payer system.

The current composition of the United States Senate will prevent a single-payer system from emerging in the near future. But make no mistake — the United States is headed toward a single-payer system. It is not a question of “if” but rather “when.”

Jarrett Lewis is executive director of health policy at The Health Management Academy, an educational and advisory services firm that works with large hospital and health systems across the United States, and he previously was a consultant to several political campaigns, most recently serving as a strategist and pollster to the Romney for President Campaign from 2011 to 2012.

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