AUGUSTA, Maine — Progressive groups looking to expand Medicaid eligibility to 70,000 Mainers will kick off a signature-gathering effort on Thursday to place the issue on a statewide ballot as early as 2017.

It’s a bid to work around Gov. Paul LePage, the biggest foil of expansion under the Affordable Care Act. He has vetoed similar legislative proposals five times.

Proponents of the citizen’s initiative, which is being proposed by leaders from the Maine Women’s Lobby and Maine Equal Justice Partners, weren’t discussing the effort on Wednesday ahead of a Thursday news conference in Portland.

But their proposal was filed with Secretary of State Matthew Dunlap’s office in September, and it would expand MaineCare, the state’s version of Medicaid, the federal health care program for low-income people, to qualifying people younger than age 65 with income at or below 138 percent of the poverty mark.

Maine is one of 19 states that hasn’t gone through with expansion, in which the federal government covers 100 percent of costs for the first three years and 90 percent after.

In those states, childless adults under 100 percent of the federal poverty mark fall into a gap in the law, not qualifying for Medicaid or the subsidized insurance reserved for people making between 100 percent and 400 percent of the poverty level. Expansion also would cover parents between 100 percent and 138 percent of the poverty level.

It’s seen as a key safeguard in the implementation of the Affordable Care Act, which has drawn recent criticism for mandates that opponents say have triggered double-digit rate increases while limiting care options.

Proponents have pointed to studies showing that expansion would promote hundreds of millions in economic growth.

But LePage and his lieutenants have warned of higher costs, pegged earlier this year at $315 million over five years by the Maine Department of Health and Human Services. Part of that includes lower federal reimbursements for the parents between 100 percent and 138 percent of poverty because of previous expansions.

LePage spokeswoman Adrienne Bennett called it “another desperate attempt from liberals to pass welfare expansion for a sixth time.”

There is no cost estimate for the planned citizen’s initiative yet, but it is sure to face criticism in particular for its lack of a funding source, which would leave the Maine Legislature to figure out how to pay for it.

In August, proponents submitted an expansion proposal to Dunlap’s office that did include a funding source — moving Maine’s top income tax rate from 7.15 percent to 9.15 percent for people making more than $1 million.

Ann Woloson, a spokeswoman for Maine Equal Justice Partners, refused to discuss many details ahead of Thursday’s new conference, but she said it likely won’t include a revenue source, making it so the September proposal is the one they’ll float. It would need 61,000 signatures to quality for the ballot in 2017 or later.

Michael Shepherd

Michael Shepherd joined the Bangor Daily News in 2015 after three years as a reporter at the Kennebec Journal. A Hallowell native who now lives in Augusta, he graduated from the University of Maine in...