We will find out for sure in a little less than five months, but at this point, it looks more likely than not that Republicans will lose control of the House while retaining their Senate majority.

Democrats appear poised to gain between 20 and 40 seats in the House; a net gain of 23 or more would tip the majority. In the Senate, currently split with 51 Republicans and 49 Democrats, we could see anything from a net gain of two seats for Democrats to a two-seat gain for the GOP. The two-seat gain for Democrats would give them the barest possible majority; the other four possible outcomes in that range would keep the majority in Republican hands with 50 (plus the vice president’s tie-breaking vote) to 53 seats.

The irony is that we could see up to a billion dollars spent on Senate races this year with no net change at all. A recent study of Kantar Media/CMAG data by the Wesleyan Media Project shows that the number of television ads aired in Senate, House, and gubernatorial races combined so far is 86 percent above the level in 2014. In Senate races, 270,615 ads have aired, 20 percent above the level at this point four years ago. The Senate seats up this cycle include some very big states, so the dollar value will end up being substantially more than in 2014.

But looking at the assortment of lightly populated states with very competitive Senate races—like Montana, Nevada, North Dakota, and West Virginia—we could easily see control of the Senate turn on fewer than 100,000 votes. Remember that even though 137 million people voted in the 2016 election, it was effectively decided by fewer than 80,000 votes spread across three not-small-at-all states: Michigan, Pennsylvania, and Wisconsin. Look back at 1982: That year Republicans won four Senate seats, preserving their newly-won majority, by a total of 39,923 votes with victories in Vermont (5,110 votes), Nevada (5,657), Rhode Island (8,212) and Delaware (20,944 votes). Throw in Wyoming (22,259) and the GOP won five seats by 62,182 votes.

The interesting question is whether President Trump or Democrats are better off with either the House or Senate or both flipping in November. On one hand, no one in the Trump orbit ought to want to hand Democrats the power to call congressional hearings and issue subpoenas. That could be a nightmare for lots of people, starting with Trump himself. And then there is the impact on his legislative agenda. Nothing has come easy since he took office; imagine if the GOP didn’t have a majority in both chambers.

But a case can be made that Trump’s reelection chances might well improve if Democrats have a majority in at least one chamber. First, there’s the chance of Democrats overreaching legislatively—say, passing single-payer health care in the House or embarking on their own Benghazi-style sham investigations of Trump-related matters. And having Democrats in control of at least one chamber gives Trump the opportunity to use them as a foil, in much the way that President Clinton used Republicans’ newly won majorities to help get reelected in 1996. Right now, and if Republicans somehow retain their majorities, Trump and his party have total responsibility for running and funding the government, for deficits, for anything coming out of Washington that anyone doesn’t like, even if they don’t actually have the capability to pass their preferred legislation. If Democrats have shared responsibility, that changes things for 2020.

Of course, elections have many moving parts and there are other things that will matter in 2020, not the least of which is the economy. With unemployment down to 3.8 percent in May and news that there were actually more job openings than unemployed, things are looking pretty great now. But keep in mind that according to the National Bureau of Economic Research, the current economic expansion began in June 2009 and is now 108 months old, the second-longest continuous period of expansion since the end of World War II. The average postwar expansion is 59 months; the postwar record is 120 months (March 1991-March 2001). Hoping that this expansion continues for two-and-a-half more years is like betting that a 105-year-old person, however healthy, is going to make it to 108. A world-class economist told me this past week that he put the odds of a recession between now and 2020 at 45 percent.

The bottom line is that elections are complicated. How much governing responsibility will Democrats have in 2020, and whom do they nominate? How is the economy doing? What will come of these Trump investigations? No single one of these questions, but all of them combined, will dictate the results.

This story was originally published on nationaljournal.com on June 12, 2018

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