This article is from the archive of our partner National Journal

Republicans are waking up this morning and celebrating their new Senate majority. But now the real work begins.

The midterms were a referendum on an unpopular president and his health care and foreign policies that pushed voters into the arms of Republicans. Whether the GOP can harness that momentum and cement itself as a national party with broad appeal barreling toward 2016 remains to be seen.

Republicans flipped Senate seats in conservative-leaning states such as Arkansas, Montana, South Dakota, and West Virginia. That was expected. The real boon for Republicans Tuesday—the indication that the GOP may be expanding its appeal—was the party's wins in moderate swing states like Colorado and North Carolina. In Virginia, where Democrats won the Governor's Mansion just a year ago, Republican Senate candidate Ed Gillespie gave Democratic Sen. Mark Warner a challenge few saw coming.

"This is a great moment for us as Republicans to carry states that are purple and often lean very blue," National Republican Senatorial Committee Chairman Jerry Moran said Tuesday night during a briefing on the election.

Still, Republicans have a lot to prove. The electorate Tuesday was older, whiter, and more male than it will presumably be in 2016. Early exit polls from The New York Times show that although Democratic Sen. Kay Hagan lost in North Carolina, she still performed well with traditionally Democratic constituencies. She led Republican Thom Tillis 54 percent to 42 percent among women and 96 percent to 3 percent among blacks. That is about the same as her performance in 2008 against Republican Elizabeth Dole. What put Tillis over the top this year was that he had a wider advantage among men than Hagan had among women.

If Republicans hope to win in 2016, however, they will need to find a candidate who not only continues to perform well among men but also can shrink the GOP's disadvantage with women and minority voters.

They need a candidate like Republican Cory Gardner, who secured a victory for the GOP in Colorado's Senate race on Tuesday. Gardner managed to flip the Democratic playbook on its head. Democrats were betting on resurrecting their 2012 "war on women" messaging strategy and hammering Gardner on "personhood" because there was an amendment on the state's ballot. Gardner, however, went on the offensive and announced he supported over-the-counter access to birth control. In 2008, Democrat Mark Udall had a 15-point advantage among women in Colorado. In 2014, it shrank to an 8-point lead. Gardner, meanwhile, expanded the Republican advantage in the state among white voters from 3 points in 2008 to 10 points in 2014. Early exit polls indicated that Democratic turnout was at its lowest level since the early 1990s, which also helped Gardner.

But how Republicans perform in 2016 will have a lot to do with how they conduct themselves in Congress over the next two years. Americans have a way of souring on incumbency. Republicans know they must transform Congress from a gridlocked body to a fully functioning one, and that could be tough with a president who is sure to have his veto pen at the ready.

"We need to govern. We need to govern well. The Senate needs to function. We need to have debate, discussion. We need to pass budgets and appropriations bills," the NRSC's Moran said Tuesday. "It also sets the stage to demonstrate that Republicans can be trusted to be elected to the presidency in 2016."

There is one more obstacle, however, that could hamper Republicans in 2016. Every day, 66,000 Latinos in the U.S. turn 18. And while some reports indicated Gardner did well among Latino voters in Colorado, many within the party in Arkansas, Kansas, and Kentucky, for example, ran their campaigns on the premise they they would challenge any move Obama made to grant "amnesty" to immigrants living in the country illegally. It may be tempting for Republicans in Congress to try to counter Obama if he makes good on his promise to unilaterally act on immigration reform in upcoming weeks. But that could undermine the GOP's ability to appeal to Latino voters down the line.

"Sadly, Republicans are going to scream, but hopefully that reaction will be short-lived," says Alfonso Aguilar, a GOP strategist and immigration expert. "Republicans need to have their own alternative plan. That is the reaction that would help them with Latinos."

Overall, Republicans had a strong showing Tuesday, but the party has failed to translate a midterm election victory into a presidential win in the past. In 1994 and 2010, Republicans had sweeps, but Democrats still managed to capture the White House two years later. In 2016, the map appears more challenging for Republicans. The GOP might have caught America's attention on election night, but whether they can keep it is anyone's guess.

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

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