Universal single-payer health-care coverage (aka "Medicare for all") can become a reality by initially making it a scarce public good in selected demonstration States and allowing its success in those States to build demand for its expansion to cover everyone in the United States.
The interest in allowing States to opt out of the public option (for example, here, here, here, here, and here) offers an opportunity to press for another State-level option: allowing States to opt in to federally funded single-payer health care.
As Paul Krugman notes about the public option opt-out, "the states most likely to opt out will probably be small states that really need the competition. But many states, with probably a majority of the population, would opt in. And if the public option works well, there will soon be pressure on politicians in the others to do the same."
A similar dynamic would likely play out with an opt-in for single-payer health care. Under this scenario, the federal government would fund single-payer health care as demonstration projects in, say, five States (essentially, "Medicare for all" in those States). To select the participating States, voters in each State would decide by referendum during the next Congressional election whether their State would volunteer to participate. If more States volunteer than the legislation allows, a random drawing, held in public, would determine the participating States.
With single-payer health-care demonstration projects in place, the public would see three health-care regimes in action: health care in States with a public option, health care in States that opt out of the public option, and health care in States that opt in to a universal single-payer system. Adding opt-in single-payer to the health-care reform mix thus allows various health-care reforms to compete head to head against each other — an all-American kind of competition that lets the public, not bought-and-paid-for politicians, decide where its health-care interests really lie.
The probable outcome? (1) More States vote to participate in the single-payer project than the legislation authorizes, resulting in a random drawing; (2) a migration of businesses to participating States, where single-payer health care would offer a significant competitive advantage (especially for small and family-owned businesses); (3) a resulting clamor by non-selected volunteer States to change the legislation to allow them to participate in the single-payer demonstration project ASAP; and (4) not much later, a demand by the remaining States to join as well.
In short, we will likely see universal single-payer health-care coverage become a reality by initially making it a scarce public good in selected demonstration States and allowing its success in those States to build demand for its expansion to cover everyone in the United States.