Sen. Elizabeth Warren says she can fund "Medicare for All" without raising taxes on the middle class. Instead, among other things, she would boost the wealth tax on the ultra-rich that she has promoted on the campaign trail.

Warren had promised at a recent debate that she would not sign a bill that raises health care costs for the middle class. Under a plan released Friday morning, the Massachusetts senator and 2020 Democratic presidential candidate goes further: Middle class Americans would no longer pay health premiums or copays and would also not pay any taxes to replace those costs.

However, she will boost what had been a 3% wealth tax on people with more than a billion dollars to 6%. Her plan would also have employers pay higher taxes to the government, which she says would replace what they currently pay toward private health insurance.

Warren is proposing $20.5 trillion in new federal spending under the proposal.

Altogether, Warren's plan says that total national health costs would not go up under the single-payer health proposal. Rather, all of the estimated $52 trillion in health spending over a decade would be paid via the federal government.