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When members of Congress come back from Thanksgiving break, they will start thinking about the 2018 elections. In elections earlier this month, Democrats made big gains - even bigger than they were expecting. So is a blue wave forming? NPR's national political correspondent Mara Liasson takes a look.
MARA LIASSON, BYLINE: In Virginia, the results were stunning. The liberal base was energized. The Democrats' 2008 coalition - educated suburbanites, millennials and single women - turned out in ways they hadn't for many cycles. But if the Democrats' goal is to take back the House and limit their losses in the Senate, they need to figure out whether they can replicate their Virginia win.
LYNDA TRAN: They ought to take everything that they've seen in Virginia with a grain of salt.
LIASSON: Lynda Tran is a Democratic strategist.
TRAN: Virginia is a very special part of the country. Its proximity to D.C. and this kind of beltway bubble mentality is something that shouldn't be underestimated.
LIASSON: In other words, voters in Virginia, particularly northern Virginia, focus on Washington and on Donald Trump in ways voters in other states just don't. Democratic pollster Stan Greenberg points out there were also important limits to the Democrats' big gains in Virginia.
STAN GREENBERG: You still have the fact that working-class voters and non-metro voters in Virginia did not move to the Democrats beyond where Trump was in 2016. That vote was stable, and obviously Democrats can't get the kind of win they need to have a real majority both nationally and in states unless they build beyond the suburbs and beyond the metro areas and reach those voters.
LIASSON: One way Democrats can reach those voters is to stick to bread-and-butter issues. Health care was the top concern for Virginia voters. Democrats are also hoping to run against the Republican tax bill, which is seen by many voters as favoring the wealthy more than the middle class. But there are other obstacles Democrats have to overcome. California Congressman Ro Khanna points to the mighty fortress of redistricting that Republicans have erected for themselves, drawing congressional and legislative district lines that make it harder for Democrats to win. And Khanna says, in many states, it's getting harder to vote.
RO KHANNA: It's a huge obstacle, I mean, in terms of not having early polling places, not allowing same-day registration, not allowing so many people to come and vote who didn't have IDs. And that's likely to continue, so we need to fight that, and gerrymandering makes it very difficult. We've got to win districts that have partisan advantage by a few points for Republicans.
LIASSON: A combination of Democratic voters clustering inefficiently in urban areas plus all those safely drawn Republican districts means that Democrats have to win way more than 50 percent of the national vote for the House of Representatives in order to get 50 percent of the seats. To find out whether those structural advantages are enough to protect Republicans from a Democratic wave, if one crashes ashore, I called GOP pollster Glen Bolger.
When you look forward to 2018, what are you telling Republicans?
GLEN BOLGER: That we should not be looking forward to 2018.
BOLGER: Look, off-year elections have been very difficult for the party in power, and Republicans control everything. And typically, the party that is out of power makes significant pickups.
LIASSON: Historically, when a president's approval rating drops below 50 percent, the party in the White House loses an average of 40 seats in the House. This year, most Republicans in the House have safe seats, says Bolger.
BOLGER: But anybody who represents a suburban seat should be very worried. After Virginia, I think that they are. And anybody who represents a seat won by Hillary Clinton in 2016 ought to be worried as well.
LIASSON: If the Democrats' task for 2018 is to come up with a message to reach white, working-class voters, the Republicans' task, says Bolger, starts with governing.
BOLGER: The best thing that can happen for Republicans is to pass legislation like tax reform and get things done as opposed to kind of getting bogged down on sideshows like Twitter. It is something that more and more people see as not presidential, and ultimately, that could end up hurting him and Republicans.
LIASSON: Donald Trump and his Twitter feed loom over the 2018 elections, and there's nothing Republicans can do about that. Midterm elections are often reactions against the president and the party in power. That's what happened to Barack Obama and the Democrats in 2010 and 2014. And President Trump has yet to prove how he helps Republicans when he's not on the ballot. Mara Liasson, NPR News, the White House. Transcript provided by NPR, Copyright NPR.