Sen. Susan Collins of Maine said Friday that she’s unlikely to support efforts to privatize Medicare and might not vote to repeal the Affordable Care Act, positions that would put her at odds with Republican party leaders.

Though Collins opposed the Affordable Care Act and says it needs many fixes, she might not support repealing the law if a suitable, detailed replacement is not identified. However, Collins stressed in a brief interview Friday that she’s not sure how she would vote on the issue.

Plans to abolish the ACA and privatize Medicare have accelerated since voters elected businessman Donald Trump to the presidency on Nov. 8. Rep. Tom Price, a Georgia Republican nominated by Trump to lead Health and Human Services, has proposed gutting the ACA and privatizing Medicare.

Collins is a moderate Republican and her vote could be crucial if those initiatives are taken up by the Senate, where Republicans will hold a slim majority come January.

Sen. Angus King of Maine, an independent who caucuses with the Democrats, said he is opposed to efforts to repeal the ACA or privatize Medicare.

Collins said plans to privatize Medicare – which have been proposed by Price and House Speaker Paul Ryan – have many problems, and she’s voted against similar ideas. Privatizing Medicare would provide skimpier benefits and be more costly to seniors, critics say.

“Suffice it to say I have a number of reservations,” Collins said Friday during an interview by phone. “A complete upending of a program (Medicare) that by and large serves seniors well is not something that appeals to me.”

President Obama has vetoed several previous efforts by Republicans to eliminate the ACA, rebuffing numerous attempts since it became law in 2010.

But once Trump becomes president in January, it’s much more likely that he will sign an ACA repeal into law.

Pending the outcome of a runoff in Louisiana this month, Republicans probably will control the Senate by a 52-48 majority. If that’s the case, it would take only three Republican defections to derail efforts to repeal the ACA or privatize Medicare.

Collins said her “number one” goal for any ACA repeal effort would be to protect people who have purchased Affordable Care Act marketplace insurance. That group includes about 10 million people, while Medicaid expansion covers an additional 15-18 million. Maine is one of 19 states that has not expanded Medicaid. The uninsured rate has plummeted in the U.S. since the ACA took effect.

“You can’t just drop insurance for 84,000 people,” Collins said, referring to people who have signed up for ACA insurance in Maine.

Collins said she’s interested in an approach advocated by Sen. Lamar Alexander, R-Tenn., who recently told reporters that an ACA replacement should be the “first” focus of Congress.

“I think what we need to focus on first is what would we replace it with and what are the steps that it would take to do that?” Alexander said, according to a report in Slate magazine.

Collins said her first impression is to agree with Alexander.

“It strikes me as a more cautious approach,” she said.

Rep. Kevin McCarthy, R-California, the Republican House majority leader, has advocated for the opposite approach, eliminating the ACA and giving Congress two to three years to come up with a replacement.

But Collins also said that without a specific bill in front of her, she can’t commit to voting one way or the other.

“I’m hesitant to speculate on something that doesn’t exist,” she said.

Collins said there are many components of the ACA that she would like to change,such as allowing insurers to sell catastrophic plans, easing requirements on small businesses and reducing the narrow networks that some insurers offer.

Emily Brostek, executive director of Consumers for Affordable Health Care, an Augusta-based health advocacy group and supporter of the ACA, was encouraged to hear that Collins is taking a thorough look at repealing the ACA and seems opposed to privatizing Medicare.

“That’s the kind of leadership that Mainers have come to expect and appreciate,” Brostek said.

Brostek said if plans to partially repeal the ACA move forward – such as eliminating the individual mandate to purchase insurance and axing subsidies to help people purchase insurance – the entire system could collapse and insurers could flee the marketplace during the uncertainty. The ACA was devised as a series of interlocking components, and removing one could cause the others to fall apart in a chain reaction.

King said if the individual mandate is revoked, people would wait to purchase insurance until they were extremely sick, perhaps “on the ambulance ride to the hospital.” That would drive up the cost of insurance, he said.

“I’ll be the first to say the ACA is not perfect,” King said. “But I’ve heard a lot about repealing, but I haven’t heard much about how it would be replaced.”

King said the proposal to privatize Medicare is “an awful idea.”

“I can’t understand why people want to change a Medicare system that has worked well for 50 years,” he said. “If it ain’t broke, don’t fix it is an old Maine motto and it should apply in this situation.”

Both King and Collins said they don’t know yet whether they would vote to approve Price for Health and Human Services. King said Price “has a tall mountain to climb” to get his vote, considering Price’s stance on the ACA and Medicare.