The odds of Democrats retaking control of the House this November continue to be long, but they are real so long as there is a possibility of a Donald Trump collapse that in this straight-ticket voting era will drag down the whole GOP ticket.
Democrats need a net gain of 30 seats to conquer the House. That would certainly not be unprecedented, since Democrats won 31 seats in 2006 and Republicans won more than twice that many in 2010. But thanks to the superior distribution of Republican voters, the lasting effects of the heavily Republican-controlled 2012 redistricting cycle, the sheer power of incumbency, and the late realization by Democrats of the opportunity they might have, netting 30 seats is a real stretch. According to the authoritative Cook Political Report, there are only 33 Republican seats that are currently vulnerable, requiring a virtual Democratic sweep for Paul Ryan to lose his gavel.
Presidential years, moreover, are not usually the best time for House “waves,” especially for the party that already holds the White House, as Nate Cohn of the New York Times points out:
Mrs. Clinton is up by around seven percentage points in polling averages. But historically, a seven-point victory for the president’s party in the national popular vote is not the way to start a wave election. Richard Nixon’s huge victory in 1972 didn’t give Republicans the House. Neither Ronald Reagan nor George H.W. Bush took the House in 1984 or 1988. Bill Clinton didn’t retake the House in 1996.
Cohn also points out that there is early evidence ticket-splitting could be making a comeback this year, for the obvious reason that an awful lot of Republican-elected officials and opinion-leaders are less than enthused about Donald Trump.
But still, some of that lack of enthusiasm is the product of fears that the mogul could wreck Republican prospects down-ballot and shift a significant number of currently semi-safe House seats into vulnerable territory.
If Democrats do fall short of what they need to regain control of the House even as Hillary Clinton becomes president, prospects for further gains in the near term will probably not be good. The party controlling the White House almost always loses House seats in midterms (1998 and 2002 were the rare exceptions), and 2018 would be a third-term midterm for Democrats, making the odds of an anti–White House trend even stronger. Beyond that, Democrats have a well-known midterm turnout problem associated with their heavy reliance on parts of the electorate — notably young people and minorities — that rarely turn out proportionately in nonpresidential elections. As for 2020, it’s worth noting that Democrats gained only eight House seats when President Obama was reelected in 2012.
The sad truth for the Donkey Party is that they may continue to struggle to retake the House until such time as they lose the presidency and thus regain the “out-party” midterm advantage. But the long-range prospects for control of the House will depend more than anything else on the performance of the two parties in the gubernatorial elections of 2018 and the state legislative contests of 2020, which will together determine the landscape for the next round of redistricting. Busting up total Republican control of state governments is the single best thing Democrats can do between now and 2022 to improve their prospects in the U.S. House; the GOP currently controls the governorship and both branches of the legislature in 23 states (Democrats only have the “trifecta” in 7 states).
All in all, Democrats ought to strike while the iron is hot this November and run up the margin on Donald Trump in a way that makes even the best incumbent-proofing measures for House candidates ineffective. It could be now or never, or at least not very soon.