Florida Gov. Rick Scott endorsed the Medicaid expansion in President Obama’s healthcare law on Wednesday, delivering a political coup to the White House.

Scott isn’t the first high-profile GOP governor to accept the Medicaid expansion, but he’s arguably the biggest get for the Obama administration. Florida led the 26-state lawsuit that said the entire healthcare law — specifically including its Medicaid expansion — was unconstitutional.

Roughly 1 million Floridians will have access to healthcare coverage if the state legislature approves Scott’s plan. He said he would only support the expansion for three years, and would back out if the federal government backs away from its funding commitments.

“While the federal government is committed to paying 100 percent of the cost of new people in Medicaid, I cannot, in good conscience, deny the uninsured access to care,” Scott said at a news conference.

Scott said last year that he would not participate in the expansion, and he has also refused any role for the state government setting up an insurance exchange — the other half of the healthcare law’s coverage expansion.