Comer unveiled his health-care plan Monday in Louisville, the hometown of two of his rivals in the GOP primary.
Comer didn't offer specifics on changing Medicaid eligibility standards, saying all options are on the table. He says many recipients deserve benefits, but says "able-bodied adults" have been added as part of Medicaid expansion.
Kentucky was among 28 states that expanded its Medicaid program under the federal Affordable Care Act. Nearly 400,000 people signed up for the expanded service, meaning about 25 percent of the state's population is on Medicaid.
Republicans worry about how much the state will have to pay for the expansion beginning in 2017.