"Michigan is a poster child for the successes of the ACA," said Allan Baumgarten, an independent analyst who studies insurance markets in nine states. "Michigan has benefited significantly from the two major expansions in coverage."
Almost 700,000 Michiganders are now enrolled in Healthy Michigan, the Medicaid expansion program for low-income residents age 19 to 64.
Meanwhile, the ACA marketplace drew more than 300,000 enrollees for 2017. About 81 percent received tax credits to offset premium costs, and 50 percent qualified for additional "cost-sharing" subsidies that reduced deductibles and co-pays.
In addition, an estimated 73,000 young adults in Michigan have benefited from the ACA provision that allows them to stay on their parents' health insurance up to age 26.