DENVER—Colorado is one of at least 18 states planning to expand health care assistance for needy adults as part of the federal health overhaul. A Q&A about how Medicaid expansion will work in Colorado:

Q: Why is Colorado expanding Medicaid? For whom?

A: The expansion is one of two main ways the federal health law expands coverage to most of the 50 million uninsured U.S. residents. In Colorado, it could add 160,000 Colorado adults with low incomes to public health care assistance.

Q: How needy would you have to be to get expanded Medicaid?

A: Colorado's expansion would allow single adults earning less than about $15,900 a year to receive Medicaid.

Q: How much will it cost?

A: According to Gov. John Hickenlooper, the expansion would cost Colorado some $128 million over the next 10 years. But he says he has identified more than $280 million in cuts and savings to Medicaid to more than pay for the change.

Q: Aren't others skeptical?

A: Of course. A report last year from the Kaiser Family Foundation and the Urban Institute said Colorado would have to spend up to $858 million over the next 10 years on the Medicaid expansion. Lawmakers from both parties have expressed skepticism that Hickenlooper's proposed Medicaid changes will cover the bill, though the governor has the ability to expand Medicaid without their OK.

Q: When does the expansion take effect?

A: 2014.