"I understand the appeal of Medicare for All. But folks supporting it should be clear that it means getting rid of Obamacare, and I'm not for that," Biden said in a video released by his campaign.

Biden aims to draw a contrast from Democratic primary competitors such as Sens. Bernie Sanders, I-Vt., and Elizabeth Warren, D-Mass., who back a single-payer plan to insure all Americans. He also looks to leverage the increase in Obamacare's popularity that followed Republican attempts to repeal the health-care law.

On Monday, Biden released an insurance plan that would expand on the law known as Obamacare. The proposal would let Americans buy into a Medicare-like public option, boost tax credits for buying coverage, and give Americans in states that did not expand Medicaid under Obamacare access to the public option without premiums, among other measures.

Joe Biden is casting "Medicare for All" as an effort to ditch the Affordable Care Act as the former vice president tries to distance himself from his 2020 Democratic presidential rivals on health care.

Medicare for All as proposed by Sanders would eliminate the private insurance market, a core piece of Obamacare. But it would create a more comprehensive government-run system. It would cover primary and preventive care, prescription drugs, dental, vision, mental health, substance abuse, maternity, newborn and long-term care with no deductibles or copays.

Medicare for All would not "do away with the ACA in the same way that repeal of the ACA would," but it "would be a significant change and likely disruptive for certain people who may like the private insurance they have," said Cynthia Cox, vice president and director for the program on the ACA at the Kaiser Family Foundation. She added that Biden is "trying to walk this line between opposing changes to the ACA from both the right and the left."

In a Monday tweet appearing to respond to Biden, Sanders said he "fought to improve and pass Obamacare" and "traveled all over the country to fight the repeal of Obamacare." But he said he "will not be deterred from ending the corporate greed that creates dysfunction in our health care system."

Sanders tweet: I fought to improve and pass Obamacare. I traveled all over the country to fight the repeal of Obamacare. But I will not be deterred from ending the corporate greed that creates dysfunction in our health care system. We must pass Medicare for All.

Sanders also pointed to the fact that former President Barack Obama called Medicare for All a "good" idea last year.

Some Democrats have cast Medicare for All — which could carry a price tag in the tens of trillions of dollars — as too expensive or impractical. Biden sees an incremental approach to policies from health care to college affordability as the best way to defeat President Donald Trump in November 2020.

Biden has led nearly every national and state poll in the Democratic primary, typically followed by some combination of Sanders, Warren and Sen. Kamala Harris, D-Calif. At the first Democratic debate last month, all three of Biden's top rivals raised their hands when asked if their health-care plan would get rid of private insurance. (Harris later said she misinterpreted the question and supports limited private insurance as a supplement to Medicare for All.)

An NBC News/Wall Street Journal poll this month found 44% of registered voters would support a single-payer system, while 49% would oppose it. Among Democratic primary voters, 72% back such a plan, while 21% oppose it, according to the survey.

At the debate last month, Biden argued the best way to expand coverage is "to build on what we did" during the Obama administration. While Obamacare was unpopular after its 2010 passage, perception of the law has shifted in recent years. In June, 46% of adults approve of the law, while 40% disapproved, according to Kaiser polling.

Voters warmed to Obamacare after nonpartisan estimates showed 2017 GOP attempts to repeal the law could cause tens of millions of Americans to lose coverage. In last year's midterms, Democrats won control of the House in large part by raising fears about Republicans scrapping Obamacare.

In recent months, Democrats have decried a Trump administration-backed lawsuit that seeks to get rid of the law entirely.

Now, Biden clearly sees promoting Obamacare as the most realistic path to defeating Trump. Kaiser's Cox notes that support for Medicare for All typically falls when people are told it would eliminate private insurance companies.

Touting the law also fits into Biden's broader strategy of tying himself to the president under whom he served eight years.

"I was very proud the day I stood there with Barack Obama when he signed that legislation," Biden said in the video released Monday.

Here are the main pieces of Biden's health-care plan:

It would allow people who have coverage through their employers or the individual market, or lack coverage completely, to buy into a "public health insurance option like Medicare."

The plan would get rid of the cap on eligibility for tax credits and make it so that no family buying a plan on the individual market will have to pay more than 8.5% of income in premiums — as opposed to the current 9.86%.

Americans who live in states that did not expand Medicaid, the federal-state insurance program for low-income people, would get "premium-free access" to the public option.

The plan calls to allow Medicare to negotiate directly with drug companies. It would also let consumers buy prescriptions from other countries in order to cut costs.

It also calls for wider access to generic drugs and penalties for drugmakers that increase prices by more than the rate of inflation.

Biden's campaign says his administration would "aggressively use its existing antitrust authority" to curb market consolidation in the health-care system.

Even though Biden opposes Medicare for All, the health care industry still may not like his plan. Partnership for America's Health Care Future, a coalition made up of pharmaceutical, hospital and insurance groups, said in a Monday statement that Biden's plan would "ultimately lead our nation down the path of a one-size-fits-all health care system run by Washington."

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