Washington Post Opinion: Obamacare lives! Now, Democrats should do right by those who fell through its cracks.

Obamacare lives to fight another day. That's thanks to the Supreme Court's ruling Thursday that quashes the latest (and hopefully last) effort to kill the Affordable Care Act. Tens of millions of Americans helped by this law — the poor, people with preexisting conditions, those without employer-sponsored insurance — can breathe a sigh of relief.

Happily, Democrats can also start playing offense again: They can concentrate on expanding, rather than simply maintaining, health coverage. Democratic lawmakers appear ready to go, with their $6 trillion reconciliation package expected next week set to include provisions that would lower the Medicare eligibility age to 60 and expand the program's benefits.

These aren't bad ideas, exactly. But they're not what Democrats should be prioritizing. At least, not if the goal is to insure as many people as possible, while Democrats still maintain slim congressional majorities.

Instead, their top agenda item should be helping people in the "Medicaid coverage gap" — that is, the millions of poor people who fell through Obamacare's cracks.

Obamacare created a few different programs that together were supposed to nearly eliminate the country's shameful uninsurance problem. Among the most important was the Medicaid expansion, which lowered the income eligibility threshold for this public health insurance program.

More than a decade after the 2010 law passed, though, 12 states, most of them Republican-controlled, still refuse to adopt the expansion, and the Supreme Court has ruled that they can't be forced to do so.

This was not what wonks had predicted. By opting out of the federally subsidized Medicaid expansion, after all, states have left lots of money on the table. Choosing not to expand also left about 2.2 million of these states' poor residents without a pathway to affordable insurance coverage. These are people who make slightly too much money to qualify for Medicaid but too little to qualify for premium subsidies in the individual marketplace.

They're mostly people in the South and people of color.

The $1.9 trillion fiscal relief plan that passed in March attempted to entice those 12 holdout states into participating by offering them even more cash.

So far, though, GOP officials seem unable to overcome their deep antipathy toward the "Obamacare," brand, no matter how much money the feds throw at them. Even in Missouri, where voters decided to expand Medicaid through a 2020 ballot measure, the Republican governor has refused to do it. (This may be a cautionary tale for other Biden proposals that would require red states to opt in, such as his initiatives for free preschool and community college.)

So what else could be done to help the millions who are uninsured? Congress has a few options.

One is to expand Obamacare's existing individual-market subsidies, to make everyone in that "gap" population eligible for fully subsidized coverage. Maybe lawmakers would add some wraparound services, too, so that these marketplace plans are as generous as Medicaid.

Another is to create a "public option," or a new federal public health insurance program. This might be a broad program that anyone could enroll in or perhaps one that narrowly targets only the people in the Medicaid gap.

On Thursday, Rep. Lloyd Doggett (D-Tex.) proposed another alternative, through legislation that would allow counties and cities to bypass their state governments and expand Medicaid on their own. (Assuming state governments don't stand in the way, of course, which is probably a risky assumption.)

There are pros and cons to each path. Marketplace subsidies could probably be set up fastest; the public option would probably be cheaper. Some safeguards would be necessary though to ensure that states that previously expanded Medicaid don't just dump everyone onto this new federal backstop. That transition would be costly and disruptive, as Brookings Institution fellow Matthew Fiedler points out. But the obstacle is not insurmountable.

You might wonder: Why focus on the Medicaid coverage gap, rather than lowering the Medicare eligibility age from 65 to 60? Yes, lowering the Medicare age would help some people newly gain insurance. But 92 percent of the population in that 60-to-64 age range already have insurance, according to the Kaiser Family Foundation. Those in the Medicaid coverage gap — whether they're old or young — almost by definition don't. So you're "not getting that much juice for the squeeze," as University of Michigan law professor Nicholas Bagley put it.

Of course, 60- to 64-year-olds live everywhere, including in blue states; the poor people in the Medicaid gap live almost exclusively in states controlled by Republicans. Which might explain why there's been more energy among Democratic lawmakers for one proposal over the other.

In theory, Democrats could pursue both policies. But they seem to have limited appetite for getting anything done on health care in the near future. If that changes, by all means, they could and should do more. In the meantime, they should focus their firepower on those whom Obamacare failed most: the red-state poor.