Though President-elect Donald Trump wants Congress to "repeal and replace" the Affordable Care Act, legal scholars say it is likely that some popular provisions of the act will remain.

But the mandate that people buy insurance and the federal subsidies that offset premiums are likely "in the crosshairs," University of Pennsylvania law professor Tom Baker said Wednesday morning.

Ultimately, that would mean less money to pay for the popular parts of President Obama's signature health insurance program, such as the requirements that insurers cover preexisting conditions and that children be allowed to stay on their parents' policies through age 25.

The bottom line is that decent health-care coverage could become more pricey than it already is.

"What it will mean is that the cost of health insurance will become so expensive that the only people who will be buying it will be people who are very high-risk and those who have money," said Baker, an insurance law scholar.

Such changes could be enacted in months by a willing Congress, though it could be longer until Americans feel their impact, since it takes a while for federal funding to switch course. Other changes could take effect as soon as Trump takes office, as he could opt to cut off funds that are now used to offset insurer losses in the exchange marketplaces, said Robert I. Field, a Drexel University professor of law, health management, and policy.

What is clear is that any alterations in the law could affect a lot of Americans, given how the number of people with health insurance coverage has increased since the sweeping law, popularly called Obamacare, took effect.

One concerned patient is Jessica Karabian, 32, who was diagnosed two years ago with incurable breast cancer that had spread to her bones. She has had a double mastectomy, ovary removal surgery, radiation, and continuous cycles of chemotherapy at the Hospital of the University of Pennsylvania. Her care is mostly covered by Medicare because she is considered disabled, but she also relies on a supplementary policy through Obamacare.

"If my supplement is dropped, I can't afford treatment, and I die," said Karabian, the mother of a 3-year-old. "I'm afraid this will give me even less time than I already have."

After the Obamacare Marketplace's open enrollment period earlier this year, 412,000 Pennsylvanians had selected a Marketplace plan and paid their first premiums as of mid-March; 78 percent of them were eligible for premium subsidies, according to the Kaiser Family Foundation. (Open enrollment for plans effective Jan. 1 began last week at

The law also allowed states to expand eligibility for Medicaid, and in Pennsylvania enrollment in that plan as well as the Children's Health Insurance Program grew by 469,000 people, a 20 percent increase compared to before the expansion, Kaiser data indicate.

In New Jersey, 249,000 residents enrolled in Marketplace coverage and paid their first premiums, with 82 percent of them eligible for the tax credits that reduce monthly payments. New Jersey expanded its Medicaid program a year before Pennsylvania did, and by this year enrollment in that as well as CHIP was up 473,000, a 37 percent increase.

Those expansions are unlikely to see immediate change, said Howard J. Peterson, managing partner of TRG Healthcare, a national consulting firm with offices in Philadelphia.

"People know that the Medicaid expansion has helped people that really are vulnerable," Peterson said. "I don't see that anyone would do anything dramatic and sudden."

As in the country at large, most Pennsylvanians get their insurance through their employers. Still, between 2013 and 2015, the uninsured rate for nonelderly adults decreased 5 percentage points, from 16 percent to 11 percent.

But a lot of people still are not on board with Obamacare: Just under 29 million Americans remain uninsured, and nearly half of them could get insurance through the law.

Just last week in King of Prussia, Trump and his running mate, Gov. Mike Pence, offered the most detail of the campaign on their plans for health care. Pence said they would expand health savings accounts — the tax-exempt funds for health-care expenses permitted in some capacities under Obamacare. A more detailed platform posted on the Trump website later explained that individuals would be able to deduct health-insurance premium payments on their tax returns.

Pence also said their plan would allow Americans to purchase insurance across state lines and allow states to manage their own Medicaid funding. The insurance program for the poor is financed mostly by the federal government, particularly the portion that was expanded under Obamacare. States have some control over how the plans are run, but Republicans have long sought greater local control.

In King of Prussia, Trump boasted that upon taking office, he would immediately "ask Congress to convene a special session so we can repeal and replace," before moving on to his more familiar themes of bolstering the military and manufacturing jobs.

Certain provisions of the Affordable Care Act have become so embedded in the health care system that they are unlikely to be repealed, said Drexel's Field.

Among them are various experimental programs designed to lower costs and improve quality, Field said.

"There's a lot in there that would be very difficult to suddenly do away with, and that large chunks of the health-care industry would not want to do away with," Field said.

In addition to supporting tax-deductible health savings accounts, Trump has said he would allow those accounts to accumulate unused funds, rather than requiring consumers to use them within a year. He said he would require price transparency by health-care providers so individuals can shop for the best prices. He also has said he wants would-be immigrants to certify that they can pay for their own health care.

In terms of prescription drugs, Trump has called for a free market, including allowing consumers to import their medications from other countries where the prices are more regulated.

During the campaign, Trump wavered on Medicare. He had seemed to agree with one-time opponent Ben Carson about replacing Medicare with health savings accounts. But he later spoke against the proposal. "Abolishing Medicare, I don't think you'll get away with that one. It's actually a program that's worked. It's a program that some people love, actually," he told MSNBC.

Trump's positions on these and other health-care issues are summarized here.

Staff writers Rita Giordano, Marie McCullough, and Don Sapatkin contributed to this article.