BOSTON — As President Trump presses to repeal the Affordable Care Act (also known as “Obamacare”), congressional Republicans are facing the challenges of developing a replacement, putting 75,000 Mainers at risk of losing health care.

With Maine independent Angus King’s U.S. Senate seat up for grabs next year – along with the fragile Senate Republican majority on which the fate of Obamacare depends – Mainers have an opportunity to shape the national health care debate.

While Sen. Susan Collins, R-Maine, has helped craft and present a plan to give states the flexibility to decide whether or not to keep Obamacare provisions, House Speaker Paul Ryan advocates complete repeal of the health insurance provisions, which have covered about 20 million Americans.

The speaker’s hands may be tied by President Trump’s stated wish to ban the use of pre-existing condition exclusions in determining who can get health insurance. The only way, though, in which insurers can take all customers regardless of their medical history is some form of an individual mandate or penalty for individuals who can afford coverage and choose not to buy it.

Insurers previously saved money by not covering folks who were likely to cost a lot (mostly those with pre-existing medical conditions). How would Trump make sure that these patients were covered?

Both President Trump and Speaker Ryan are advocating a system in which individuals excluded from insurance because of a pre-existing condition could get coverage in his or her state’s high-risk pool. These pools cover individuals who can’t get group coverage because they have or are likely to have high medical expenses; healthier people are insured under standard insurance at group rates.

This is how Republicans want an estimated 230,000 Mainers with pre-existing conditions to obtain insurance in the post-ACA era.

Though Speaker Ryan calls this plan “A Better Way,” there’s nothing new about high-risk pools. Before the ACA’s signing in 2010, high-risk pools covered about 200,000 patients in 35 states. The history of these pools tells us that they are no panacea for anyone. High-risk pools prior to 2010 were a catastrophic failure that left most uncovered or with tight coverage restrictions.

Because of the pools, insurers were allowed to reject individuals likely to have high expenses.

Most states had far more people applying than they had resources to support, so lengthy waiting lists were common. In Washington state, over 80 percent of those referred to the high-risk pool never got health insurance, The New York Times recently reported, while California had an endless waiting list. Richard Figueroa, a senior administrator for the California program, recalled in an interview with the Times that “there were people literally dying on the waiting list.”

Most state pools had lifetime and/or annual benefit caps on payments for medical care, something now illegal because of the ACA. But doing away with benefit caps in state high-risk pools would make them economically unviable.

What are the “pre-existing conditions” that get excluded? Every insurance company developed its own list. Here are just a few of the hundreds of commonly used reasons to exclude or limit health insurance: acne, AIDS, arthritis, artificial joints, asthma, bipolar disorder, cancer, chronic obstructive pulmonary disorder, coronary artery disease, diabetes, domestic violence, drug abuse, emphysema, fertility treatment, insulin use, kidney failure, leukemia, multiple sclerosis, pacemakers, pregnancy, rape, rheumatoid arthritis, sleep apnea, suicide attempts and being either overweight or underweight.

Sen. Collins’ plan to give states authority to decide whether or not to keep the basic provisions of Obamacare is attractive to some as a compromise.

Still, it dodges the crucial question: How will insurance companies provide coverage to all, regardless of current or past medical conditions, without some requirement for everyone to purchase health insurance? High-risk pools are not the answer.

While we wait to see a Republican plan to replace Obamacare, more than 20 million Americans and over 75,000 Mainers wait to see whether they will lose the health insurance the ACA gave them. The 2018 mid-term elections for the Senate and House of Representatives in 2018 will be crucial.

In the meantime, Mainers who care about protecting health care for all Americans should join the coalition of moms, dads, kids, physicians, hospital workers and others working to protect their care at familiesusa.org/initiatives/ protect-our-care.