"You don't have to have a public option," Romney said. "You don't have to have the government getting into the insurance business to make it work."
Three years after enacting its own version of reform, Massachusetts now has near-universal coverage.
Taxpayer watchdogs say it's affordable.
"There is this widespread assumption, that is treated as fact, that it's breaking the bank in Massachusetts ... it's not breaking the bank at all." said Michael Widmer of Massachusetts Taxpayers Foundation.
And health care experts say it's popular.
"Seven in 10 people in the state support the program, and no more than one in 10 would repeal it." said Robert Lendon with the Harvard University School of Public Health.
Unlike Democratic proposals that would give Americans the choice of joining a government-run health care plan, Massachusetts has no public option. Instead, people in the state are required to buy private insurance, and the poor get subsidies.
Analysts say "Romney care" is basically "Obama care" minus the public option.