DEARBORN, Mich. -

Gov. Rick Snyder checked off one of the major priorities of his first term on Monday, signing into law a measure that will make hundreds of thousands of state residents eligible for Medicaid.

It took a sometimes nasty political fight to make this bill signing possible, but the Healthy Michigan Law will eventually make 470,000 more people eligible for Medicaid.

Snyder's signature at the ceremony at Oakwood Hospital in Dearborn makes Michigan the largest state controlled by Republicans to support a key component of the new federal health care law.

It will expand the government health insurance program to almost a half-million Michigan residents within a few years, nearly halving the state's uninsured. An estimated 320,000 are expected to be eligible in late March if the federal government approves the plan.

"They just don't make a high income but they work hard and we want them to have a better quality of life," said Governor Rick Snyder. "Getting mom care earlier in pregnancy will be extraordinarily important to make sure we have the healthiest Michiganders we can have."

The newly eligible are supposed to buy low cost insurance through exchanges starting October 1st.

The program is one part of Obamacare, a program some republicans have vowed to derail.

Democrat John Dingell says the faults can be corrected, "There are imperfections there and the last perfect bill came off Mount Sinai with Moses."

"This is something that's really important. This is about the health of our fellow Michiganders," Snyder said to applause prior to the bill-signing, noting that "we didn't do anything about it for many years."

Medicaid expansion is part of a strategy to ensure that nearly all Americans have health insurance under the Affordable Care Act. It was designed to cover the neediest uninsured people yet became optional for states because of a Supreme Court decision.

Many GOP-led states opposed to the law have declined the expansion, despite the U.S. government promising to cover the entire cost for the first three years and 90 percent later. Michigan becomes just the third state where the GOP also controls the Legislature to accept it — joining Arizona and North Dakota.

"(Signing the bill) is the easy part of the job," Snyder said Monday. Now it needs to be implemented, he said.

The program already covers one in five Michigan residents, mainly low-income children, pregnant women, the disabled and some poorer working adults. The expansion will cover adults making up to 133 percent of the poverty level — $15,500 for an individual, $26,500 for a family of three.

Snyder and a coalition of backers ranging from the business and medical lobbies to advocates for the poor say offering health insurance to more low-income residents will make them healthier and minimize expensive trips to the emergency room, preventing cost-shifting to businesses and individuals with health plans.

For more information visit Michigan.gov.