In 2017, Wood spoke at a Bernie Sanders press conference on universal health care. This past June, she testified at a congressional hearing on universal health coverage. She now works full-time for Mass-Care, a Massachusetts-based nonprofit advocating for Medicare for All.

Not every single-payer advocate’s story is as heartbreaking as Wood’s. But Medicare for All—otherwise known as single-payer health care—has taken on an astonishing popularity among Democrats and independents in recent years, rising from a fringe, socialist hobbyhorse to a policy seriously and frequently considered during the Democratic primary debates. In 2016, it was the special quirk of Sanders’s candidacy; now 11 candidates support some version of it. Single-payer health care, the kind that exists in Canada and some European countries, would make medical care free or nearly free for all Americans. Under some versions of these plans, private insurance would be eliminated, and all Americans would be covered under one, government-run plan, similar to Medicare.

Wood and a half-dozen other supporters of Medicare for All told me about the deep physical and emotional wounds that brought them into the fold. Most either have or recently had health insurance, but they say it wasn’t enough to protect them or their family members from death, illness, or debt. Medicare for All strikes many as the easiest way to stop the health-care madness, even if the political path to it isn’t yet clear. They’ve grown disgusted with the American health-care system and reached the conclusion that blowing up the system is the only way forward.

In a way, the rallying cry of single-payer harkens back to President Barack Obama’s use of, in the dark days of the 2008 recession, uplifting slogans like “Hope,” “Change,” and “Yes, we can.” Most people didn’t know exactly how “hope” would lead us out of economic gloom. But just as with health care today, they were pretty sure it couldn’t get any worse.

Though the exact number depends on the poll and the way the question is asked, a slim majority of Americans—51 percent—now support Medicare for All, according to a Kaiser Family Foundation poll. Many moderate Democrats and most conservatives remain staunchly opposed to any kind of single-payer plan. Former Vice President Joe Biden, who supports more incremental health reforms, has said Medicare for All would raise taxes on the middle class. Many Democrats are uneasy about dismantling the private health-insurance market, and they worry about how such a sweeping program would be funded. Instead of premiums and deductibles, under Medicare for All Americans would pay for their health care through taxes—although who would pay and how much are matters of great dispute.

Read: Warren won’t soak the middle class after all

Marie Fishpaw, the director of domestic-policy studies at the Heritage Foundation, a conservative think tank, disputes that Medicare for All is even all that popular. (Support for Medicare for All has declined somewhat since 2017.) “While polls show initial support for Medicare for All, there is a remarkable drop in support when people learn more about the details,” she told me via email. “Any program that is going to create more taxes, take away health-care choices, or outlaw private health coverage entirely becomes a nonstarter.”