John McCarthy, Ohio’s Medicaid director, at Monday’s meeting of the state Controlling Board, which decided to accept federal money to expand Medicaid. (Eamon Queeney/Columbus Dispatch via AP)

Ohio agreed Monday to offer Medicaid to about 300,000 more low-income people, a major victory for Gov. John Kasich over fellow Republicans who control the state legislature and oppose the expansion.

After nine months of battling with the state GOP’s conservative wing, Kasich resorted to an uncommon maneuver in which he turned to a relatively obscure state board with power over certain budget decisions. The board voted to accept $2.55 billion in federal money to cover the cost of expanding Medicaid in Ohio through July 2015.

The 5 to 2 vote by the Controlling Board, composed mainly of a small group of lawmakers, is only a temporary answer to a question that has been roiling politics in Ohio — and other states — for more than a year. It does not spell out whether Ohio will provide money to keep Medicaid more generous in future years, when the state would need to chip in a small portion of the expense. And even before the board acted, some conservative Republican lawmakers were threatening to go to court, alleging the governor illegally bypassed the legislature.

The bitter politics of Medicaid in Ohio are indicative of lingering questions surrounding how the United States will guarantee health coverage — and, in turn, access to medical care — to some of its poorest citizens, despite the 2010 federal law intended to vastly reduce the number of uninsured.

The law’s goal of expanding coverage was built on two pillars: an expansion of Medicaid to people with incomes up to 138 percent of the federal poverty level and, for people with higher incomes, new exchanges and subsidies to help them purchase private insurance. But last year, the Supreme Court ruled that each state has the freedom to expand Medicaid or not.

The result has been a checkerboard, with Democratic-led states agreeing to the Medicaid expansion and most Republican-led states refusing. Ohio is the 25th state to extend Medicaid and the eighth with a GOP governor. The question remains in limbo in some states, including Pennsylvania and New Hampshire — as well as Virginia, where the decision is likely to hinge on the outcome of the gubernatorial election next month.

In Ohio, the politics of Medicaid have strained the Republican Party. Kasich has championed the expansion on grounds both biblical and economic. He has said that, as a moral matter, the state should provide medical help “for those that live in the shadows of life.” And he has argued, with support from business groups, that reducing the state’s population of uninsured people ultimately translates into more jobs.

Last winter, Kasich asked the legislature to allow a Medicaid expansion as part of the state budget, but lawmakers removed that element when they approved the budget this year.

State figures suggest that 275,000 Ohioans will become eligible for Medicaid for the first time. The Kaiser Family Foundation estimates that 330,000 people in Ohio would have fallen into a coverage gap without the expansion.