If you’re one of the 7 million or so Americans enrolled in Obamacare, you might suddenly be worried about your health insurance.

Prominent Republicans such as Kentucky Sen. Mitch McConnell, Texas Sen. Ted Cruz and Senator-elect Joni Ernst of Iowa have said it’s essential to repeal the Affordable Care Act. Now that Republicans have won the Senate, they control both houses of Congress, giving them the power to craft legislation to undo the ACA, passed by Democrats in 2010. President Obama would veto any legislation that eliminates the whole program or threatens essential elements of it, such as the individual mandate requiring everybody to have health insurance. Still, Congress and the White House will probably play out the whole repeal drama anyway, no matter how scripted it will be.

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Once that symbolic maneuvering is over, Republicans are likely to seek more modest changes that could affect the type of coverage consumers are able to get, along with how much it costs. Because it requires two-thirds of the Senate to override a veto, Republicans — who will control 54 Senate seats at the most — won’t be able to override a presidential veto if (okay, when) Obama objects to any legislation that dismantles the ACA as a whole. But other possible changes have more bipartisan support, making it harder for Obama to oppose them, which means some changes to the ACA are probably inevitable.



For all its problems, Obamacare is becoming a core element of the U.S. healthcare system. By next year, the number of Americans receiving health coverage through the ACA should rise to more than 10 million. Though the law is unpopular, 60% of Americans say it doesn’t really affect them (most because they get health coverage through their employer), and the portion who want to modify the law is far larger than those who say it should repealed.



As more people enroll, there could even come a time when efforts to dismantle Obamacare become a political loser for Republicans. “Over time, threatening to repeal Obamacare is going to become a liability because more and more people are going to draw benefits from it,” says Henry Aaron of the Brookings Institution.



Alterations to Obamacare













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For now, however, Republicans seem to have a green light to attempt modifications to the law. Some will have no effect on people enrolled in the program, even if they affect the way the law is administered.



There may be enough bipartisan support, for instance, to repeal a tax on medical devices that helps generate revenue to pay for subsidies for low-income enrollees. Republicans want to make other changes, such as dissolving a federal board meant to oversee healthcare pricing and eliminating provisions meant to help insurance companies if certain costs related to Obamacare end up higher than expected. Obama might even sign some of those into law.





Other possible changes could affect ACA enrollees more directly. One Republican bill would lower the subsidies available to low-income people, which would make the whole program more affordable for the government but obviously raise the cost to some participants.



Another idea is to add a new, lower level of coverage—dubbed a “copper” plan—which would have lower premiums but also require more out-of-pocket spending when care is needed. This would create a new option for people who want to comply with the law requiring everybody to have health insurance, at the lowest possible cost.





Republicans could also change some of the law’s requirements, especially the “employer mandate” requiring every company with more than 50 workers to offer health insurance or pay a penalty. If that requirement were eliminated, some smaller companies might drop coverage for employees, though those people would still be able to get insurance through the federal health marketplace or one of the state exchanges—and they might even get a better deal than their employers were offering.

One other change Republicans might seek is a new definition of who counts as a “full-time” worker. The law defines full-time as anybody who works 30 hours per week or more, which means such employees must be offered healthcare coverage at firms required to provide it. Business groups want the definition changed to 40 hours per week, which would allow them to hire more people who work less without having to offer coverage. That could exempt more people from employer-offered plans and send them, too, to one of the exchanges.



The real threat to the ACA





There’s another threat to Obamacare that has nothing to do with the political makeup of Congress. A lawsuit known as Halbig v. Burwell has been winding through the courts, and if plaintiffs succeed it could mean the elimination of federal subsidies for as many as 7 million people covered under the program by 2016. It could still take a year or two for the legal maneuvering to play out, and the case could ultimately land at the Supreme Court. The thing to know is that this is a sleeper case with potential ramifications more serious than anything likely to get through Congress during the next two years.

On the whole, there will probably be a lot of sparks flying over Obamacare in 2015, but few actual changes ordinary people will have to contend with. Still, the law is far from final and the 2016 elections could determine its ultimate fate. If Republicans are able to win the White House and hold on to both houses of Congress, then big changes would, in fact, be in store--and Republicans would face a gut-check moment testing their willingness to end federally subsidized insurance for millions who have it.

Rick Newman’s latest book is Rebounders: How Winners Pivot From Setback To Success. Follow him on Twitter: @rickjnewman.