In the seven years after the Affordable Care Act became law, Republicans voted more than 60 times to repeal it. Each time, the legislation passed the House easily, only for Democrats to block it in the Senate; in 2015, though, a repeal bill passed the Senate, too, forcing President Barack Obama to veto it. So when the GOP began this year in control of Congress and with President Trump in the White House, the law’s fate might have seemed sealed.

Instead, efforts to repeal and replace Obamacare collapsed Tuesday, although the Senate will still try to push ahead this coming week. But if the effort fails, a promise that has been at the heart of Republican campaigns since 2010 — abolishing the ACA — could go unfulfilled at the peak of the party’s recent power.

That should not come as a surprise: My research has found that it’s extremely rare for a majority party on Capitol Hill to deliver on its agenda if the minority holds strong against it. And passing a partisan messaging bill that everyone knows will have no real-world consequences, such as the past repeal votes, is nothing like actually legislating — a distinction well understood by congressional party leaders and rank-and-file members.

Majority parties in Congress rarely succeed in passing laws along party lines. In a recent paper, James Curry and I show that most legislation — major and minor bills alike — passes with majority support from both parties. Minority party support for enacted legislation seldom falls below 70 percent in the Senate or 60 percent in the House. Fewer than 15 percent of new laws are enacted over the opposition of a majority of the minority party in the Senate. These patterns are consistent across Congresses with either unified or divided party control. Likewise, the tremendous growth in party conflict in Congress has hardly budged these figures. No matter how many one-sided messaging bills majority parties ram through one chamber of Congress, actual legislating today remains overwhelmingly bipartisan.

Curry and I also specifically examined the ability of majority parties in Congress to enact their agendas. We identified the 197 items that majority leaders flagged as priorities at the start of each Congress between 1993 and 2017. We found only 10 cases in which a majority party succeeded over the opposition of most minority party members and the minority party’s leaders in both chambers.

The Affordable Care Act was one of those exceedingly rare cases. But repealing it hasn’t been.

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Most of the time, when parties pass something they promised voters, they do so by co-opting the minority party in at least one chamber of Congress, usually with the support of at least one top opposing leader. This pattern holds regardless of unified or divided party control of government. What Republicans have been attempting to do with health care this Congress is something parties rarely succeed at doing.

Issues that make for great campaign pledges typically present thorny problems of governance, as Republicans have been demonstrating. No issue was better than health care for GOP messaging during the Obama presidency: It excited base voters, motivated donors, fueled candidacies, and provided a ready argument to criticize the performance of the opposing party and its president.

But when parties engage in messaging, they do not have to confront hard choices. Partisan talking points make simplistic promises — only upsides, without any downsides. “You should have the freedom and the flexibility to choose the care that’s best for you,” read House Speaker Paul D. Ryan’s “Better Way” agenda last year. “. . . You and your family should have access to the best life-saving treatments in the world.”

Actually legislating on health care, however, entails unavoidable policy trade-offs. If you limit how much insurers can charge older consumers, younger ones will have to make up the difference. If you allow health insurers to attract young, healthy people with cheaper plans, you concentrate the old and the sick in plans that will have to charge higher premiums. If you guarantee that people can purchase health insurance despite preexisting conditions, you give them an incentive to not sign up for insurance until they are sick, raising premiums and destabilizing insurance markets. If you lower taxes, you reduce the money available for Medicaid coverage for the disabled, elderly and poor. Every policy move has losers and winners.

Health care is not unusual, either: Parties normally have a hard time living up to their platforms. Fiscal responsibility and balanced budgets have been hoary mainstays of both parties’ messaging since long before the Republicans’ 1994 Contract With America. A balanced budget has great appeal to voters who worry about saddling future generations with unsustainable debt. But taking concrete policy action to close deficits is entirely different: Fiscal retrenchment imposes real-world pain. This is why you don’t typically hear as much about balancing the budget from parties in control of Congress or the White House.

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Or consider the policy ideas in the Senate Democrats’ 2014 “Fair Shot” agenda. One proposal, a higher minimum wage, is very popular in public opinion polls and made a great message for Democrats. But actually writing legislation to increase the federal minimum wage requires balancing the interests of large and small businesses, the different costs of living in wealthy and poor states, and possible effects on employment levels. Similarly, “equal pay for equal work” for men and women is a great Democratic Party rallying cry. But it is not easy to figure out in practice how much regulation of private employers’ personnel decisions is either feasible or desirable.

In 2014, though, Senate Democrats did not need to work out the complex details of their agenda items: Controlling only one chamber of Congress, they knew that any of these initiatives would run into a brick wall of opposition in the Republican House. Any legislation they could get out of the Senate would just be a “messaging bill,” no different from the many times Republicans attempted to repeal Obamacare during the Obama presidency. (Democrats lost control of the Senate in that year’s elections, anyway.)

The main political problem Republicans face is that American parties rarely find themselves on the hook to deliver on their promises the way the GOP is now. Divided government is the normal state of affairs. Control of national government has been divided 79 percent of the time since 1980 and 69 percent of the time since 1954. Although our research shows that parties enjoying unified control do not rack up substantially better records of accomplishment, at least under divided government, parties have ample opportunity to pass the buck when they are unable to deliver. Even under unified government, majority parties can usually point to the minority’s ability to block via the Senate filibuster.

But in choosing to pursue repeal and replacement of Obamacare via a congressional budget process not subject to the filibuster, Republicans took upon themselves alone the burden of managing all the policy trade-offs and the full responsibility for all the pain their choices would impose. Parties typically struggle to coalesce on complex legislative issues. It is hardly surprising that a decisive number of Republicans, faced with bearing the blame for all these difficult political and policy decisions, would balk. As one longtime congressional aide told me in an interview for my last book: “There’s a big difference between governing and campaigning. Governing is a hell of a lot harder.”

outlook@washpost.com

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