The Supreme Court majority surprised many on Thursday by affirming the constitutionality of the Affordable Care Act, with twists that give states like Maine an even more important role in shaping implementation.

Let’s start with the major news. The nonprofit group Families USA estimates that, by 2019, more than half a million Maine households will be better off by an average of $1,685 a year because of the key reforms:

  1. Insurance policyholders benefit from rules to prevent insurance companies from avoiding or dumping people who are sick, to require free preventive-care checkups and to allow young adults to stay on parental health plans.
  2. Eighty percent of insurance premiums must now be spent on actual health care, not CEO salaries or bureaucracy, or else companies must give refunds. This summer, more than 10,000 Maine families are getting rebates averaging $463 apiece.
  3. More than 200,000 Maine senior citizens are already benefiting from improvements in Medicare, including more generous prescription drug coverage and free health checkups for all seniors. By 2020, the “donut hole” in Medicare drug coverage will be entirely closed.
  4. Almost 100,000 Maine families with low or modest incomes who do not now have health coverage will get new coverage through MaineCare or by using generous tax credits to purchase private health plans of their choice.
  5. So far, 139 community health centers in Maine have gotten grants totaling more than $18.7 millions to serve patients in underserved or remote areas.
  6. Maine has received $6.8 million in federal grants so far to plan for new “health insurance exchanges” to let businesses and people easily comparison-shop for health coverage and use tax credits to reduce the price.

Maine, like all other states, now faces important challenges. The state health exchange must be set up, and Maine voters and lawmakers need to decide whether to accept 100 percent federal funding for an expansion of MaineCare to cover more disabled, poor and elderly people. The Supreme Court said that states are free to decide whether to accept the new federal money — and states cannot lose prior funding if they refuse.

In some states, Republicans want to decline the federal money for ideological reasons. But those states that decline will watch Medicaid money go instead to other states, such as Massachusetts, and they will force their own hospitals, doctors, nonprofits and communities to absorb more costs for helping the poor and disabled.

The Supreme Court majority also upheld the individual mandate. But so what? That means a lot less than we might imagine after all the public brouhaha. Once reform goes into full effect, about two Americans out of every 100 will still not have health insurance through work, Medicaid or Medicare, or by using new tax credits to buy insurance. This tiny sliver will be subject to a small tax fine, so uninsured people cannot just go to the emergency room and shift the cost onto the rest of us. Opponents of reform are trying to make voters believe that most people will be subject to higher taxes for Obamacare. That is simply not true. In Maine, the vast majority of people will never have to think about the mandate — and will save thousands a year through reform.

Political battles will go on for a while. Republicans promise to repeal Affordable Care if Mitt Romney becomes president and they run all of Congress in 2013. But repeal is impossible unless opponents gain 60 seats in the U.S. Senate — not likely in our lifetimes. Opponents can delay funding and mess up implementation for a while, but they cannot make the law go away.

Affordable Care’s very popular features will not remain hidden for long. Sixty to 80 percent of all Americans — including a majority of Republican voters — favor the new rules for insurance companies, the tax credits and subsidies to make insurance affordable for all, and the state-level exchanges to allow comparison shopping. As the months and years pass, people will rely on the benefits of reform, and doctors and hospitals will carry through experiments in quality care and cost control encouraged by the new law. U.S. health care will be better for everyone — and we will look back and wonder what all the fuss all about.

Theda Skocpol is a professor at Harvard University, member of the National Academy of Sciences and former president of the American Political Science Association. She is the co-author with Lawrence Jacobs of “Health Reform and American Politics: What Everyone Needs to Know.” She has a home in Maine and is national director of the Scholars Strategy Network, which has a regional group in Maine and brings together scholars across the country to address public challenges and their policy implications.