A Democratic-leaning group has launched an ad campaign against Republican candidate for governor Jeff Johnson, accusing him of pushing policies that would take health care away from people who need it.

In a statement, Johnson called the ads “blatant lies intended to cover up the fact that the DFL candidate for governor wants to eliminate private health insurance and force all Minnesotans onto one government program.” It’s in reference to U.S. Rep. Tim Walz’s stated aim to provide a government health plan to all Minnesotans, like seniors currently use under Medicare.

The ads from the Alliance for a Better Minnesota thrust health care into the governor’s race, and along with it one that Americans have been debating for nearly a decade: Obamacare, formally known as the Affordable Care Act.

Among the primary features of the ACA was an expansion of Medicaid, a government insurance program for the poor and disabled, to include more people. In addition, insurance companies were mandated to cover all customers, including those with pre-existing conditions. In exchange, the insurance companies were supposed to get lots of new — presumably younger, healthier — customers, who would be required to buy insurance. (The mandate was repealed last year.)

Johnson has said he wants to win a federal waiver so Minnesota can part ways with the law.

Alliance for a Better Minnesota says this means people who have pre-existing conditions would return to a market in which they struggle to find coverage.

But Johnson also says Minnesotans with pre-existing conditions would still be able to get coverage under his plan, because he wants to reinstitute something called a high-risk pool. The Minnesota Comprehensive Health Association (MCHA) — a program for people who couldn’t get insurance anywhere else because of their health problems — was serving about 26,000 people when it went away with passage of the ACA.

When the Legislature was mulling a return to a program such as MCHA after the 2016 election, Eileen Smith of the Minnesota Council of Health Plans — a nonpartisan trade association of health insurers — told the Star Tribune that the customers paid higher-than-usual premiums and had deductibles of as much as $10,000 per person. The 1.3 million Minnesotans with private health insurance had to pay a tax to subsidize the MCHA, which needed $178 million to stay above water in its final year, 2013.

The state also had to step in to provide money three times in the 38-year existence of the program, Smith said.

Johnson also wants to allow insurers to sell products that don’t cover as many health conditions, which would give consumers more options and create competition in the marketplace, he says. Health economists warn that this would skew the risk pool, allowing younger, healthier customers to buy inexpensive, “skinny” coverage. In turn, older customers with health problems — and their employers, or taxpayers — would pay more.

Although Walz has adopted the Medicare-for-all plan of many progressives in his party, he has said the first step is to allow Minnesotans to buy into an insurance program for the working poor called MinnesotaCare.

The Alliance for a Better Minnesota is shelling out in the high six figures for ad time. The group is ostensibly independent but invariably backs DFL candidates and is supported by large donations from labor unions and a few wealthy individuals, including Alida Messinger, who is the ex-wife of Gov. Mark Dayton and an heiress to the Rockefeller fortune. Former Gov. Tim Pawlenty, who lost to Johnson in the GOP primary, was on the receiving end of a slashing ad campaign from ABM before his eventual defeat.