Physicians for a National Health Program

Their single-payer web page is here with the facts. Bottom line: The majority of doctors support single payer because it covers everyone and is financially feasible and fair. For example:

"The system would be funded in part by the savings obtained from replacing today’s welter of inefficient, profit-oriented, private insurance companies – and the system-wide administrative waste they generate – with a single streamlined, nonprofit public payer. Such savings, estimated in 2017 to be about $500 billion annually, would be redirected to patient care."

"Existing tax revenue would fund much of the system. According to a 2016 study in the American Journal of Public Health, tax-funded expenditures already account for about two-thirds of U.S. health spending. That revenue would be retained and supplemented by modest new taxes based on ability to pay, taxes that would typically be fully offset by the elimination of today’s premiums and out-of-pocket expenses for care. The vast majority of U.S. households – one study says 95 percent – would come out financially ahead."

Also see this article on the war over the Mercatus Report.