“They can see for themselves how that experience stacks up against high-priced care that requires them to fight tooth-and-nail against their insurance company,” Warren wrote in a Medium post unveiling the plan, echoing more moderate candidates like Mayor Pete Buttigeig who has pushed his own “public option” plan as "a glide path to that Medicare for All." Warren's version of the public option covers more people than Buttigieg's and has more expansive benefits.

Warren's team argues that the plan would result in a full single-payer system by the end of her first term just like Sanders' plan. Her plan also answers rivals who have said that already hard-pressed families can’t wait for such a sweeping overhaul to experience relief from health costs. The new set of policies seeks to bridge divisions over building on Obamacare's coverage expansion versus single-payer by declaring that the country can have it all.

But Warren's opponents were quick to continue attacking her on the issue.

"Despite adopting Pete's language of 'choice,' her plan is still a 'my way or the highway' approach that would eradicate choice for millions of Americans," Buttigieg's communications director Lis Smith said. "No amount of Washington political games can save her plan from that fatal flaw: she still doesn’t trust the America people to make the right health care decisions for themselves.”

Former Vice President Joe Biden's campaign was equally blunt. "Having discovered how problematic her embrace of Medicare for All has become — its ending of private health coverage, its punishment of states and employers who have done the right thing, its elimination of millions of jobs, its tax increase on the middle class — Senator Warren is now trying to muddy the waters even further," deputy campaign manager Kate Bedingfield said in a statement. "What started out as 'mathematical gymnastics' have been replaced by a full program of flips and twists covering every element of her plan."

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Turning Medicare for All into a multi-year legislative exercise could also deepen suspicion of Warren from some on the left who have questioned how dedicated she is to passing a true single-payer health care bill. Asked last week what the first three bills she wants passed as president, Warren cited corruption reform, ending the Senate filibuster and imposing a wealth tax.

Rep. Pramila Jayapal (D-Wash.), who introduced the House version of Sanders' Medicare for All bill, praised both Sanders and Warren Friday. "We have two presidential candidates who are staunchly committed to Medicare for All and have made it a defining issue in the 2020 presidential election," she said in a statement. "Her transition plan, released today, reaffirms her commitment to the four-year transition plan outlined in the Senate Medicare for All Bill."

But Warren insists passage of single-payer will be made easier by curbing the power of the insurance, hospital and private equity industries that fiercely oppose the plan. In her first 100 days, she said she will put a new tax on lobbying expenditures over half a million dollars, ban lobbyists from donating to political campaigns and ban elected officials and political appointees from becoming lobbyists after they leave government.

“Money slithers through Washington like a snake,” she wrote. “Any candidate that cannot or will not identify this problem, call it out, and pledge to make fixing it a top priority will not succeed in delivering any public expansion of health care coverage — or any other major priority.”

Warren’s policy team moved quickly to release both the transition and a recent financing plans before next week’s Democratic debate. In the October debate, several of Warren’s opponents attacked her for not being forthcoming on how Medicare for All would work.

Medicare for All is likely to again factor prominently in the next debate. Opponents have already signaled that they will keep up the offensive, with several arguing in recent weeks that her financing plan was unrealistic.

And while much of Warren’s new plan depends on a like-minded Congress — a long shot considering many Senate Democrats and candidates oppose Medicare for All — she outlined executive actions she could unilaterally take as president, from direct negotiations with drug companies to making Medicare cover dental services and ordering the Justice Department to defend, not attack, Obamacare against conservative lawsuits.

“I won’t hand Mitch McConnell a veto over my health care agenda,” she said.

Still, splitting the effort into multiple bills could create complications and impede her eventual goal. Veterans of the Affordable Care Act battles say that just passing one health care bill sucked up more time and oxygen than the Obama administration planned.

"We learned from the ACA implementation that policy makers in DC may not be the best predictors of how long it will take to roll out a major policy change," said Sabrina Corlette, a research professor and co-director of the Center on Health Insurance Reforms at Georgetown University.

A quick timeline, Corlette said, "makes sense politically but raises the risk dramatically that people won’t be able to access the new coverage option." A longer transition timeline, meanwhile, means "you could have a new Congress and a new president that would undermine your vision, and it could increase your costs."

Warren's new plan also does not address what would happen to people in the insurance industry whose jobs would be phased out as private coverage ends. Warren has pledged to sign an executive order to create a "commission of workers" that will focus on that, in addition to the billions of dollars set aside in Sanders' bill "to provide assistance to workers who may be affected by the transition to Medicare for All."