The Club for Growth has not yet completed its final evaluation of Ohio Gov. John Kasich, but issued a warning about his acceptance of Obamacare's Medicaid expansion.

The club is an influential, conservative, nonprofit organization that focuses on economic issues and cutting taxes, which releases "white papers" on the presidential candidates that involve heavy research into their individual backgrounds.

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"John Kasich's decision to expand Medicaid in Ohio in 2013 was a costly mistake," said Club for Growth president David McIntosh in a statement. "Medicaid enrollment in Ohio has far outpaced Kasich's projections and more than doubled in cost. The Club for Growth is concluding its research into Kasich's broader record on issues of economic freedom. But, our presidential white paper on the Ohio governor will, no doubt, warn of the long-lasting consequences from his decision to burden Ohio with an ever-growing price tag for Medicaid expansion."

Kasich expanded Medicaid in his state under Obamacare, much to the displeasure of conservatives, and sought to assuage any lingering concerns by citing previous expansions of the program via President Reagan. But the cost of the expansion for the state has doubled from earlier projections and officials now expect to pay $130 million, according to the Associated Press.

Kasich is expected to launch his presidential campaign in Columbus, Ohio, Tuesday where he will join an increasingly crowded field, which includes 15 major Republican candidates already. Kasich's political group released a video Monday arguing for his candidacy in advance of his announcement.