They contend Schuette's past efforts to dismantle the Affordable Care Act that provided 90 percent federal funding for the entitlement program and his support of work requirements will lead to the demise of Snyder's Healthy Michigan program. Snyder signed legislation in June imposing the work requirements, starting in 2020.

"If Bill Schuette is elected and delivers his promise, a year from now, he will essentially reach into those medicine cabinets and take the medications away," Duggan said. "That's what he's running on."

But the Schuette campaign isn't ruling out a dismantling of Snyder's Medicaid program.

John Sellek, a campaign spokesman for Schuette, said Democrats are trying to turn health care into "a political football and stoke fear, instead of treating it as the serious issue it is."

Democrats aren't just emphasizing this issue to low-income voters on Medicaid or voters who know somebody who relies on the state for health insurance.

They're planning to make a case to businesses that have benefited from a program that has extended health insurance to one in every 15 residents.

The Healthy Michigan program is in many ways providing health insurance to individuals whose employers can't afford to — or won't.

Rural and urban hospitals, doctors and managed care companies have benefited from the new customers with insurance, greatly reducing the hundreds of millions of dollars hospitals lost annually in charity or uncompensated care. This was one of Snyder's arguments to accept the federal funding to expand Medicaid eligibility.

Charity care for Michigan hospitals plummeted by 67 percent from $420 million in 2013 — the year Michigan expanded Medicaid — to $139 million in 2016, according to the Michigan Health & Hospital Association.

"It's cut down on uncompensated care, it's made it so people will come in to get the service they need," said Laura Appel, senior vice president and chief innovation officer at the hospital association.

If Schuette were elected governor and decided to eliminate the Healthy Michigan program or tinker with the Medicaid system, he would likely face a wall of opposition in Lansing.

That's because hospitals seem to be generally pleased with the system in place.

The Affordable Care Act forced hospitals to take cuts in Medicare to fund the expanded Medicaid coverage and other parts of the law. That amounted to $7 billion over 10 years for Michigan's hospitals, Appel said.

Statewide in 2015, the state's hospitals recorded aggregate losses after Medicaid reimbursements at $262 million, a nearly four-fold reduction from the more than $1 billion shortfall a decade ago, Appel said.

"It's a huge improvement," Appel said. "But it still doesn't get us to the (total) cost of care."

At the four-hospital Detroit Medical Center system alone, uncompensated care declined by 54 percent from $200.5 million in 2013 to $92.5 million in 2016, Crain's health care writer Jay Greene reported in March.

In the Democratic primary, health care policy was a major issue as former Detroit health department director Abdul El-Sayed pushed for a Medicare-for-all statewide insurance benefit.

Whitmer called a single-payer system for Michigan "unrealistic."

The former legislator from East Lansing was clearly trying to avoid letting Schuette box her into the democratic socialist camp of Vermont Sen. Bernie Sanders (who endorsed El-Sayed).

In early July, Whitmer told Crain's she would unveil a new health care proposal "soon."

The proposal never came.

But she promises to put forward a plan in the general election campaign that will build on Snyder's program.

"I ran on my record of actually having delivered health care coverage when I worked with Rick Snyder to embrace the Affordable Care Act and extended it to 680,000 people in our state — and I'm determined to do more," Whitmer said the day after the primary. "We know that's all at risk if Bill Schuette's our next governor.