U.S. Sen. Elizabeth Warren, who is trying to sell Americans on Medicare for All with the help of a new financing plan, should first have analyzed the dilemma in deep-blue New York, where a bill to replace private insurance with a single-payer system has stalled despite Democratic domination of all levels and levers of power.

The mighty challenge here, where the New York Health Act is weighed down under questions about cost and practicality, suggests that Warren’s plan could sink her chances should she advance to a general election against President Donald Trump.

Americans, like New Yorkers, are divided on imposing a single, state-run insurance plan and wiping out private health insurance in the bargain. Nationally, 51% support the general concept; 47% oppose. Other polls show even less support. In New York, polling shows 40% support and 45% oppose.

Voters need convincing, not on principle, but on substance.

Warren’s financing plan is less than persuasive: Every piece of the puzzle, from the unrealistically low $20.5 trillion price tag to the fusillade of new taxes necessary to fund it, fuels fears that it would be a logistical nightmare and an unsustainable drag on the federal budget. The New York Health Act, which needs $139 billion in new tax revenue in year one (today, the total state budget is $175 billion), is struggling under similar stressors. The only major study performed analyzing its viability shows single-payer’s success relies on mammoth assumptions, especially on slashing health costs.

Warren and New York Dems, take note: Polls show 70% of Americans, and 90% of Democrats, support Medicare for All who want it — the ability for people to buy into a public system if they desire.

That’s an easier pill for most individuals to swallow, and a far easier sell in a presidential election.