With just three months remaining until the Iowa caucuses, the Democratic primary is entering a critical phase, in which more of the peripheral candidates will surely follow the example of Beto O’Rourke, who dropped out of the race on Friday. The front-runners—Elizabeth Warren, Joe Biden, and Bernie Sanders—will be looking to consolidate their positions. And candidates in the second tier—including Pete Buttigieg, Kamala Harris, and Amy Klobuchar—will be going all in for Iowa.

In the betting markets, Warren is now the favorite to win the nomination. But with front-runner status comes new challenges, and the biggest one for Warren recently has been the charge of evasiveness from her fellow-candidates about the fiscal costs of Medicare for All, a policy idea that she endorses. On Friday, Warren unveiled a Medicare for All financing plan, which her campaign developed in consultation with a number of experts, including two veterans of the Obama years: Donald Berwick, the former head of the federal agency that oversees Medicare and Medicaid programs, and Betsey Stevenson, a former member of the White House Council of Economic Advisers.

The plan is simultaneously clever and risky. Warren will be hoping that it blunts the attacks from her rivals and allows her to pivot to other proposals, of which she has dozens. She is not taking the politically convenient way out, which would have been to return to the less committal stance she took at the start of the year. Back then, she said that she supported universal health care and Bernie Sanders’s Medicare for All bill, but she also said that she wasn’t wedded to any particular way of achieving her goals or to any particular financing scheme.

Now Warren has laid out her own plan, which would transform an industry that represents roughly a sixth of the U.S. economy and come with a price tag of at least $20.5 trillion over ten years. Rather than tacking to the center, she is betting that Democratic voters—and members of the American electorate—are so fed up with the current health-care system, even after the Obamacare reforms, that they are ready to rip it up and start again. That is an audacious move.

The cleverness of the new plan lies in the fact that it reinforces Warren’s political platform as an agent of change with a plan for everything. And, of course, it also makes it harder for her opponents to claim that she would sock it to ordinary American taxpayers in order to pay for universal health care. Instead, by relying on payroll contributions from employers and a range of other new taxes levied on corporations and the wealthy, she claims that she can create a system that provides health care for everyone and eliminates all the hassles of dealing with insurance companies, with, as the plan notes, “not one penny in middle-class tax increases.” Indeed, since households’ monthly premiums, co-payments, and deductibles would all vanish under the plan, some eleven trillion dollars a year “goes right back into the pockets of America’s working families.”

The risks of the plan are the flip side of its ambition and scale. According to the Kaiser Family Foundation, 156.2 million Americans—almost half of the population—are covered by employer-provided health-care plans, which would be eliminated under Medicare for All. Conceivably, Warren could persuade these people that their families would be better off under a government-run, single-payer system, but it would be a challenge, even in some Democratic-leaning circles. For example, certain labor unions have held off embracing Medicare for All because they think that their members would prefer to keep their existing plans.

Going forward, Warren’s centrist Democratic opponents will continue to bring up the issue of employer-provided insurance, and they will also try to poke holes in her financing plan, some details of which bear scrutiny. For example, the plan says that stricter tax enforcement and more funding for the I.R.S. would generate $2.3 trillion in new revenue over ten years. On the spending side, it says that, by introducing a variety of new cost controls, it would be possible to restrict the annual growth of over-all health-care spending to the same growth rate as G.D.P. Neither of these claims is out of the question, but both of them are optimistic. On Friday, a spokesperson for Biden accused Warren of engaging in “mathematical gymnastics,” and Biden himself told Judy Woodruff, of “PBS NewsHour,” “She’s making it up.” Warren shot back, referring to Berwick and Stevenson, “The cost projections that we have on Medicare were authenticated by President Obama’s head of Medicare. Our revenue projections were authenticated by President Obama’s labor economist.”

The back-and-forth will continue, of course. But whatever you think of Warren’s plan and its specific numbers, it deserves credit for reminding us of two things that often get overlooked in political debates. First, if you take the view, which is supported by history, that imposing higher taxes on corporations and the very wealthy wouldn’t have a deleterious effect on economic growth, there is a great deal of potential revenue that is currently going untapped. Second, if you want to create a universal health-care system at a reasonable cost, you have to put the squeeze on health-care providers—not just insurance companies but also doctors, hospitals, and drug companies. Under the current, bloated system, they all charge prices that are much higher than in other countries. “A heart bypass surgery that costs nearly $16,000 in the Netherlands costs an average of $75,000 in the United States,” the plan points out. “A CT scan that costs $97 in Canada costs an average of $896 here.“

Under Warren’s plan, private health insurance would be largely eliminated. Doctors would be remunerated at current Medicare rates, which in some cases are only half of what private insurers pay. (The discrepancy is biggest for specialist providers.) Hospitals would be remunerated at slightly higher than Medicare rates, which have been shown not to cover their costs fully. And, as the single purchaser of health-care services, the federal government would use its bargaining power to negotiate down the prices of brand-name drugs by as much as seventy per cent, and the prices of generic drugs by as much as thirty per cent. If negotiations with the drug companies failed, the federal government would take more aggressive steps, including forcing drug companies to license their products and using public funds to manufacture certain medicines.

On health care, as in other areas, Warren has shown a willingness to consider remedies that go beyond the Washington consensus and get to the heart of the matter. She cannot be faulted for lack of boldness.