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New Jersey Governor Chris Christie announced, an opponent of the Affordable Care Act, aka Obamacare, said Tuesday that his state will participate in Medicaid expansion that is a centerpiece of the law's attempt to give health insurance to the uninsured.

Christie's is the eighth Republican Republican governor to buy into the Medicaid expansion, which was made optional by the U.S. Supreme Court decision on Obamacare.

"While we already have one of the most expansive and generous Medicaid programs in the nation, including the second-highest eligibility rate for children, we have an opportunity to ensure an even greater number of New Jerseyans who are at or near the poverty line have access to critical health services beginning in January 2014," Christie said at the State House today during an address on the New Jersey budget.

Half the states have agreed to participate in Medicaid expansion, according to health consulting firm the Advisory Board.

The program will get its funding from the federal government for its first three years and begin contributing 10 percent of the costs in 2020, Christie said.

The announcement came as a bit of a surprise as Christie has often criticized the Affordable Care Act, but it also comes in the wake of an announcement from the Obama administration that states can lower their Medicaid payments to doctors and health care providers.

The New Jersey governor was quick to distance himself from Obama's signature health care legislation today.

"I am not a fan of the Affordable Care Act," Christie said. "I think it's wrong for New Jersey, and I think it's wrong for America."

The governor twice vetoed state legislation that would have created health care exchanges under the ACA, saying the federal government had not made clear how much such a system would cost his state.

But today he reasoned that if New Jerseyians refused the Obamacare funds in the Medicaid expansion program, they would simply be spent on health care ventures in neighboring states.

"I will make all my judgments as governor based on what I believe is best for New Jersey."

The New Jersey Star-Ledger first reported Christie's plans hours before his press conference.