Sen. Susan Collins, R-Maine, walks towards the Senate floor on Capitol Hill in Washington, Tuesday, Sept. 5, 2017. 

AUGUSTA — Republicans’ latest plan to repeal the Affordable Care Act looked to be in danger Monday, when a spokeswoman for U.S. Sen. Susan Collins said the Maine Republican has “concerns” about the proposal.

Collins hasn’t taken a formal position on the bill sponsored by Republican Sens. Lindsey Graham of South Carolina and Bill Cassidy of Louisiana, but the road to passage may go through her. She was one of three Republicans who sunk the party’s last repeal bid in July.

The Graham-Cassidy bill is being touted by supporters as a moderate alternative to past repeal proposals. It would eliminate subsidies for Affordable Care Act exchanges and a higher reimbursement rate for Medicaid expansion states, replacing that with lower block grants.

But opponents merely see it as a massive cut. The liberal Center on Budget and Policy Priorities said the Graham-Cassidy bill that would cut federal health care coverage in Maine by more than $1 billion by 2027, but the nonpartisan Congressional Budget Office hasn’t yet weighed in.

In a Monday statement, Collins spokeswoman Annie Clark said her boss has “a number of concerns” with the proposal, including Medicaid cuts and impact to Affordable Care Act requirement that insurers cover people with pre-existing conditions.

The Washington Post reported Sunday that Republican leaders want a vote on the Graham-Cassidy bill by month’s end. Sen. Rand Paul, R-Kentucky, opposes it, so Republicans may need to woo Collins or Sen. Lisa Murkowski, R-Alaska, to pass it on a party line.

Gov. Paul LePage came out in support of the proposal in a Sunday email sent by the Maine Republican Party urging supporters to lobby Collins and independent U.S. Sen. Angus King to support the repeal bid, but neither supported the previous effort despite LePage’s urging in July.