One by one, key health care industry groups are telling the incoming Republican administration and Congress that it's not a good idea to repeal the 2010 health care law without clear plans to address the consequences.

Hospitals, insurers and actuaries — bean-counters who make long-range economic estimates — have weighed in, and more interest groups are expected to make their views known soon. Representing patients, the American Cancer Society Cancer Action Network reminded lawmakers that lives are at stake.

The concerns go beyond the obvious potential hardship for the 20 million people covered by subsidized private insurance and expanded Medicaid under President Barack Obama's signature law.

Hospitals say a stand-alone repeal would cost them billions, compromising their ability to serve local communities. Insurers say Congress must be careful not to create even more uncertainty and instability. Actuaries worry the mere promise of an eventual replacement won't be enough to sustain the individual health insurance market.

And the anti-cancer network is concerned that protection for people with pre-existing health conditions might be undermined or lost. Before the Affordable Care Act, it was common for insurers to deny coverage to people with a cancer diagnosis, even if successfully treated, or to charge them more. Also, uninsured people with cancer are more likely to be diagnosed late, when there's less chance of a cure.

"Replacement health care legislation that accompanies repeal needs to provide recognized patient protections that currently exist," Chris Hansen, the group's president, said in a statement.

Republicans say they remain resolute in their determination to repeal "Obamacare," but some also seem mindful of the potential political risks.

The basic plan under GOP consideration involves repealing the health law next year, but delaying the effective date to allow Congress time to pass a replacement. That replacement presumably would do many of the things the Affordable Care Act does, such as subsidize coverage and protect people in poor health, but with less regulation and without the unpopular "individual mandate" that forces most Americans to have coverage or risk fines.

However, replacement legislation that covers a comparable number of people would still require billions in government financing and extensive regulations, a stumbling block for the most conservative Republicans.

The path forward is complicated by the dynamics of the 2016 political campaign, which centered on personalities rather than policy. President-elect Donald Trump promised to repeal "Obamacare," but his ideas for a replacement plan were more talking points than an actual plan.

"Public opinion seems to be shifting," said John Rother, president of the National Coalition on Health Care, an umbrella organization that includes doctors, businesses, unions, and religious groups. "It's not clear when people say they want to 'repeal,' what they mean by that. It may mean they just want to get rid of the individual mandate."

Rother believes the outcome ultimately hinges on a handful of GOP senators.

"Moderate Republicans are worried about the consequences," he said. His coalition has written Congress to express its concerns.

Industry groups are giving lawmakers plenty to consider.

The two main hospital lobbies — the American Hospital Association and the Federation of American Hospitals — released studies indicating more than $200 billion in potential losses for their members if the health law is repealed without restoring the funding cuts that were used to finance coverage expansion. "Losses of this magnitude cannot be sustained and will ... decimate hospitals' and health systems' ability to provide services, weaken local economies ... and result in massive job losses," the groups said in a letter to Trump.

America's Health Insurance Plans, the biggest insurer lobby, said its members need time, as well as an assurance that federal dollars will continue to flow, in order to successfully transition to a new system under different rules. It took the better part of three years once Obama's health law was passed to launch its major coverage expansion, and that was anything but smooth. Insurers said the new administration and Congress need to "send strong signals" that they're willing to maintain the current market through at least Jan. 1, 2019.

Perhaps the most sobering assessment comes from a little-known group, the American Academy of Actuaries, representing professionals who assess the financial stability of pension and health insurance programs. Unlike hospitals and insurers, actuaries don't have a direct financial stake in the future of the health law. The group said delaying the effective date of a repeal while a replacement is worked out could create such uncertainty that it triggers a crisis for the individual health insurance market.

That's where people who don't have job-based coverage can buy policies, including more than 10 million in HealthCare.gov and other government markets, and 9 million who purchase their plans independently.

"Significant market disruption could result, leading to millions of Americans losing their health insurance," the actuaries' group wrote Congress.