Alaska Gov. Bill Walker on Thursday announced that he will accept federal money to expand Medicaid in the state, despite the objections of the Republican-majority legislature that sought to limit health-care access.

His decision makes Alaska the 31st state, including the District of Columbia, to expand the public health insurance. The U.S. Supreme Court’s ruling last month in favor of a key provision in the Affordable Care Act (ACA) opened the door for governors to expand health care under the law in the face of intense and long-lasting opposition from Republican-dominated legislatures.

Walker, a Republican-turned-Independent who made Medicaid expansion a priority during his 2014 gubernatorial bid, had tried working with the Alaska legislature on the issue. He first included an expansion proposal in his 2016 budget proposal, and when that was removed, he introduced a Medicaid expansion bill.

“Alaska and Alaskans cannot wait any longer,” Walker said in a statement announcing expansion. “This is the final option for me. I’ve tried everything else.”

Expanding Medicaid in the state will give coverage to as many as 42,000 low-income Alaskans, half of whom would enroll in the first year, according to state estimates. It will also save the state money—$146 million the first year of expansion, according to the Governor.

Based on recent Medicaid enrollment numbers, the state’s prediction may very well be low. Medicaid enrollees have far surpassed initial estimates in more than a dozen states. In both Kentucky and Illinois, the number of new Medicaid enrollees, 311,000 and 623,000, respectively, was more than double what the states had projected.

Medicaid eligibility changes in Alaska could take effect as early as September 1. Under Alaska law, Walker had to give 45-day notice to the state’s Legislative Budget and Audit Committee, which he did on Thursday. The committee can issue a recommendation whether to accept federal dollars for Medicaid, but Walker said on Thursday he has the authority to move forward with or without the committee’s approval.

Of the 29 states that had expanded Medicaid under the ACA before Walker’s announcement last week, ten have Republican governors and only five have Republican legislatures. Montana and Indiana lawmakers also decided to expand Medicaid this year.