This article is from the archive of our partner National Journal

It didn't take long for the potential 2016 presidential contenders to retreat to separate corners last week after President Obama announced his executive action providing legal status to some 5 million undocumented immigrants.

As quickly as Hillary Clinton tweeted her support for Obama's explosive decision, a procession of possible 2016 Republican candidates condemned it. In the process, both sides underscored the likelihood that the next presidential election will function as a sort of sudden-death overtime for the confrontations already escalating between Obama and congressional Republicans, not only on immigration, but also climate, health care, and foreign policy.

The public's assessment of a retiring president always shadows the race to replace him: In exit polls, attitudes about the overall job performance of Ronald Reagan in 1988, Bill Clinton in 2000, and George W. Bush in 2008 powerfully predicted whether voters supported his party's choice to succeed him.

But in those elections, the party nominees actually spent relatively little time debating whether to maintain the outgoing president's specific policy agenda. In 1988, Democrat Michael Dukakis largely avoided Reagan. In 2000, Bush handled Clinton mostly through his oblique promise to restore "honor and dignity to the White House" (though as president Bush later revoked Clinton initiatives in such areas as stem-cell research and climate). In 2008, Obama criticized the outgoing Bush's direction more directly, particularly on national security, but still primarily looked forward.

In its early laps, the 2016 race is unfolding very differently. The Obama immigration decision provoked an eruption from the leading potential Republican presidential candidates, including those, like Sen. Marco Rubio of Florida and that state's former Gov. Jeb Bush, who have previously supported a legislated pathway to citizenship for undocumented immigrants. Whatever else they say about immigration, those reactions suggest it is likely that every major 2016 Republican presidential candidate will pledge to repeal Obama's sweeping executive action.

Most in the GOP's potential class of 2016 have also indicated their determination to repeal or dismantle the Affordable Care Act; undo the Obama regulations under that law requiring employers who provide health insurance to include no-cost contraception; and stop the proposed Environmental Protection Agency regulations that would require power plants to significantly reduce the carbon emissions linked to global climate change. It's easy to imagine a moment in a Republican presidential debate next summer when no hands rise after the moderator asks if anyone on stage is not committed to reversing "Obama's executive amnesty" or repealing his "government takeover of the health care system."

The lines aren't etched quite as sharply yet, but it wouldn't be surprising either to see the GOP candidates renounce the climate agreement Obama recently announced with China, and any nuclear agreement he might reach during the negotiations with Iran that were extended this week.

Hillary Clinton, by contrast, has already locked arms with Obama on almost all of these issues. She quickly insisted the GOP Congress's "abdication of responsibility" forced Obama to act unilaterally on immigration; has pledged in effect to mend, not end, the health care law; praised the EPA climate regulations; and condemned as "deeply disturbing" the Supreme Court Hobby Lobby decision limiting the contraception mandate. Iran looms as the possible exception: Clinton has left herself more wiggle room to withhold full support for a deal if Obama concludes one.

Even so, a pattern is already hardening with Clinton embracing and the 2016 Republicans repudiating many of Obama's most consequential, and polarizing, initiatives. Republicans believe this dynamic will benefit them because, as Obama himself acknowledged with his "new car smell" remarks this week, voters usually prefer change after a two-term president. "It makes it far more difficult for Hillary Clinton to separate herself from Barack Obama and avoid the charge that she's going to represent [his] third term," says Republican pollster Whit Ayres.

But Democratic pollster Geoff Garin, who advised Clinton during her 2008 primary race, says Republicans determined to rescind Obama's accomplishments risk feeding the impression they simply want to revert to the George W. Bush presidency the country rejected. "This idea that they are just going to be a rewind [won't] be very appealing to people," Garin predicts.

Whichever side ultimately benefits most, the cascading confrontations over Obama's agenda may act most clearly to reinforce the electorate's ingrained demographic and geographic divisions. Some Hillary Clinton supporters are already touting her ability to recapture working-class and graying white voters who have stampeded from Obama. But these disputed Obama initiatives will complicate that pursuit because they consistently face the most opposition from precisely those blue-collar and older whites. (Exactly three-fifths of non-college whites, for instance, opposed Obama's immigration decision in last week's NBC News/Wall Street Journal survey.) Conversely, Republican pledges to annul the Obama actions will make it tougher for them to attract minorities (immigration and health care), millennials (climate), and white-collar women (contraception).

Presidential candidates always believe their unique appeal can remake the existing electoral coalition and map. But if the Obama wars rage into 2016, both sides may find the presidential battlefield looks more familiar—and entrenched—than they expected.

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

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