This article is from the archive of our partner National Journal

Understanding the politics of the president's health care law has never been complicated. It was barely passed through Congress despite huge Democratic majorities in 2009, became the driving force behind the GOP's takeover of the House in 2010, and again was the leading issue Republicans campaigned on to retake the Senate in 2014. Nearly 15,000 advertisements aired about Obamacare in the last week of last year's midterms, and 94 percent of the messaging was negative. One week later, Republicans won nine Senate seats and netted their largest House majority since the 1920s. For Republicans, it has been the political gift that keeps on giving.

Yet even though public opinion remains unfavorable towards the law, Democrats remain in denial about its political standing. Its supporters rushed to declare the issue closed for debate after the Supreme Court's ruling last month that federal subsidies remained constitutional. "After more than 50 votes in Congress to repeal or weaken this law, after a presidential election based in part on preserving or repealing this law; after multiple challenges to this law before the Supreme Court—the Affordable Care Act is here to stay," President Obama proclaimed after the ruling.

In reality, the law will likely remain a pivotal element of the GOP's argument against Hillary Clinton in 2016—and for Republicans in the battleground congressional contests. Adding to the political momentum for opponents of the law are unpopular mandates and provisions that were delayed after the midterms but will be taking effect as the presidential election draws closer. Most significantly, leading health insurance companies are seeking significant increases for premiums, as they're finding their customers are sicker than expected. At the same time, federal "risk corridors" established to help cover their rising costs are expiring and not likely to be renewed by a cost-conscious Congress.

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Even the Obama administration, by its own actions, has demonstrated the unpopularity of its signature law. In responding to political resistance to Obamacare, the White House purposely delayed critical elements of the law until after the 2014 midterm elections—when Obama would be heading out of office. Medium-sized businesses won't be required to provide health insurance to their employees until next year—a mandate that opponents of the law argued would be overly burdensome and drag the economy down. Consumers who received extensions for their old health care plans won't be able to keep them past 2017, renewing the prospect of another flood of politically-damaging cancellation notices. The funding streams to the insurance companies—or bailout, in the GOP parlance—that would help reduce consumer costs are unlikely to be maintained, given how expensive it would be. The theory was that if they kept buying time, public opinion would slowly get with the program regardless of its fiscal sustainability.

Polling suggests that the White House was a bit too clever for its own good. Support for the law has barely trickled upwards in recent months. That's not an encouraging sign, given the many political land mines that are around the corner. Last month's NBC News/Wall Street Journal poll found an outright 50 percent majority of Americans supporting either full repeal or "a major overhaul." Forty-seven percent supported smaller changes, with only 8 percent wanting to maintain the status quo. The numbers were stable from the previous year. A Kaiser Family Foundation tracking survey found support for the law receiving a small bounce immediately after the Supreme Court's ruling, with 43 percent viewing it favorably and 40 percent unfavorably. But the same survey found more respondents saying it "directly hurt" their family (24 percent) than saying it helped (19 percent).

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There's been an assumption that just because Democrats continue to suffer at the polls because of the law's unpopularity, Republicans will eventually be able to roll it back. Opposition to the law is still wide and fairly deep, and most GOP campaigns plan on using it against their Democratic rivals. (By recruiting several former officeholders in key Senate races, Democrats have leading Senate candidates on record in favor of the law.) But in order to translate that opposition into action, Republicans would need to win the presidency and then spend valuable political capital on making changes. The Supreme Court's ruling on the legality of the Obamacare subsidies ensured that any changes made to the law will be taking place in the political realm, where public officials will be held accountable for their actions.

Among Republicans, there's a heated debate under way about the Obamacare strategy in a best-case scenario in which they win the presidency and hold the Senate in 2016. Sen. Ben Sasse of Nebraska outlined three dueling GOP camps in a recent National Review column. One faction would prefer to keep it alive as a political issue in perpetuity, talking about repealing the law but otherwise keeping the core of it in place. A second would undertake a scorched-earth legislative strategy to fully repeal the law—even killing the filibuster to lower the necessary votes to pass legislation—disregarding any of the political consequences. The third group, which Sasse labels the "Replacement Caucus," would make significant changes to the law after campaigning on a reform-oriented health care agenda in the presidential election. That's the most tenable approach—and the fact that Sasse, a hard-line Senate conservative, is calling for something other than outright repeal is telling. (Sasse still supports repealing the law but only with a replacement plan in hand.)

If Republicans win the presidency, the political momentum—and votes for rolling back core elements of Obamacare—would be in place. In that scenario, Republicans would have won three out of four elections, and a depleted Democratic Party would be in disarray. Republicans could credibly claim a health care mandate, given how prominently the issue played in recent elections. And Democrats would probably want some kind of Republican buy-in on health care, short of the politically untenable calls for repeal. President Obama would be retired, lacking the clout to pressure Democrats to defend everything in the legislation so closely tied to his presidency.

(RELATED: The Supreme Court Obamacare Case, Explained)

Look at the 2018 Senate map, and the prospect of a center-right health care reform constituency isn't so outlandish. Republicans currently hold 54 Senate seats and, if they win the presidency, are unlikely to lose their majority. Meanwhile, there are five red-state Democrats up for reelection that year—Sens. Joe Manchin of West Virginia, Heidi Heitkamp of North Dakota, Claire McCaskill of Missouri, Joe Donnelly of Indiana, and Jon Tester of Montana—and several more battleground-state Democrats expecting competitive reelections. Politics, not principle, will be their mantra.

To be sure, such a scenario isn't the likeliest, given that it requires a GOP presidential victory and the prospect of Republican unity—two things that have been in short supply in recent years. But it isn't far-fetched either, especially given that winning elections often leads to legislative momentum. Obama was able to revamp the nation's entire health care system, even with widespread public opposition to his plan. Imagine what Republicans could do if they take control, with a majority of the public supporting change to Obamacare.

This article is from the archive of our partner National Journal.

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