Election Day is upon us, and most of the major nonpartisan handicappers and number-crunching forecasters are predicting the same thing: Democrats will overcome a host of structural disadvantages to retake the House, while Republicans will hold onto the Senate, in no small part because of the quirks of the electoral calendar.
For the record, that’s what I expect to happen as well. But that established consensus can obscure a reality that can’t be ignored: The available evidence suggests those are the most likely outcomes, but it does not guarantee them—a lesson that 2016 made painfully clear. It is all but certain that there will be a few big surprises on Tuesday night that no one will have seen coming on Tuesday morning. A shocker or three in the Senate, or a whole bunch of them in the House, won’t necessarily alter the big picture. But if the surprises keep piling up and happen in just the right places, we just might be looking at a Democratic Senate, a GOP House, or both.
Here, then, are a few plausible ways the prevailing wisdom could go bust.
A Democratic Senate
Flipping the Senate was always going to be a heavy lift for Democrats, despite control of the upper chamber sitting just two seats away. More than half of the Democrats’ 49-member caucus is on the ballot on Tuesday, and 10 of those 26 incumbents are in states Donald Trump won two years ago. Republicans, meanwhile, are defending just nine of their 51 seats, only one of which is in a state Hillary Clinton won (Nevada, by 2.4 percent) and half of which are Mitt Romney–running-in-Utah safe. But while it’s a historically horrendous map for Democrats, it’s not an impossible one to navigate.
Here’s how Democrats could net the two seats they need for a 51-seat majority.
Scenario 1: Heidi holds on
Of the half-dozen or so vulnerable Democratic incumbents, North Dakota Sen. Heidi Heitkamp is thought to be in the most danger. She’s down double digits in the polls to GOP Rep.
Kevin Cramer in a state Trump won by 36 percentage points. The Cook Political Report and other handicappers rate the race as “Lean Republican,” the only Democratic seat right of the tossup column. FiveThirtyEight’s classic model has Cramer as a 3-in-4 favorite. And CNN pegs Cramer’s most likely margin of victory at 8 percentage points, though its range of forecasted outcomes runs from a 19-percentage-point win by Cramer to a 4-percentage-point win by Heitkamp.
If Heitkamp were to pull this one out, though, that would fundamentally change the equation. Democrats currently have four credible chances of picking up a seat: Arizona, Nevada, Texas, and Tennessee. But there’s a clear divide between the first two and the last two on that list. FiveThirtyEight and CNN both have Democrat Kyrsten Sinema as a mild favorite to win a close race against Martha McSally in Arizona. Meanwhile in Nevada, FiveThirtyEight sees Democrat Jacky Rosen as the slight favorite and CNN sees her as the tiniest of underdogs against GOP Sen. Dean Heller. Meanwhile, both sites see Beto O’Rourke and Phil Bredesen as considerably longer shots in Texas and Tennessee, respectively. If Heitkamp and the rest of the Democratic incumbents can survive, winning eminently winnable races in Arizona and Nevada would be enough to win the Senate. If Heitkamp loses, though, Democrats will need to offset it with a bona fide upset somewhere else.
Scenario 2: Beto O’Rourke to the rescue
The path to 51 gets narrower if Heitkamp or another one of her Senate colleagues goes down, but it doesn’t close completely. Democrats would need a hero to emerge, most likely either in Texas or Tennessee. Of the two, Beto is considered the slightly better bet: FiveThirtyEight’s classic model, for instance, gives the Texan a 2-in-9 chance of beating Ted Cruz, to Bredesen’s 1-in-5 chance of beating Marsha Blackburn. If Beto takes down Cruz, he’d cement his status as a progressive folk hero. But if Beto takes down Cruz and becomes the 51st Democratic senator in the process? He’d become a god to the left.
Scenario 3: A very special surprise
If Heidi falls and Beto and Bredesen come up short—or some other less likely combination of events gets Democrats to 50 seats—Democrats could still be alive. Their last hope would be Tuesday’s special election in Mississippi, which is very special indeed: There were no primaries to winnow the field, there are no party affiliations listed on the ballot to guide voters, and there will be no election-night winner unless one of the four candidates secures a majority of the vote. That means a two-person runoff on Nov. 27 remains possible—and based on limited polling, maybe even probable—between the two favorites, interim GOP Sen. Cindy Hyde-Smith and former Agriculture Secretary Mike Espy.* Cook has the race leaning Republican, meaning it’s technically competitive, but other handicappers like Inside Elections and Larry Sabato’s Crystal Ball disagree. Regardless of Espy’s chances, though, a runoff would keep the Democratic dream of Senate control alive for at least a little longer.
A Republican House
Republicans are running into some serious historical headwinds as they try to limit Democrats’ gains below the 23 seats they need to take the speaker’s gavel. The party that controls the presidency has lost congressional seats in 35 out of the 38 midterms dating back to the end of the Civil War. And according to the Cook Political Report’s count, there have been seven midterm elections since 1966 where a president’s approval rating “hovered” below 50 percent—a, um, generous term for where Trump’s sits at the moment—and in those, the opposing party has picked up at least two dozen House seats in all but one. The sole exception was in 2014 in the middle of Barack Obama’s second term. The GOP won “only” 13 seats that year, in no small part because Democrats didn’t have all that many to lose after getting shellacked in the 2010 midterms.
Unlike in the Senate, where roughly one-third of the seats are up at any given time, the entire lower chamber is on the ballot every two years. That makes plotting out if-then paths to a GOP House insanely complicated, so let’s instead consider the types of races Republicans will need to win on Tuesday in order to keep the House. For the sake of simplicity, we’ll work off of Cook’s ratings and FiveThirtyEight’s classic model (as of midday Monday) to plot a path to another GOP House.
Where Republicans are the favorites
Cook counts a total of 47 Republican seats as tossups or worse for the GOP, giving Democrats plenty of opportunities to pick up the 23 seats they need. But before Republicans worry about winning the bulk of those battlegrounds, first they need to lock down the seats where they have the advantage but by are no means shoe-ins—a “Lean Republican” list that includes 28 GOP seats. Republicans don’t need to win all those districts, but they’ll need to offset any losses in this column with corresponding wins in districts that aren’t nearly as friendly. A small sampling of the kind of races we’re talking about:
• Iowa’s 4th, where bigoted Rep. Steve King is a 6-in-7 favorite against former pro baseball player J.D. Scholten in a rural district that went for Trump by 27 percentage points after going for Mitt Romney by 8 percentage points six years ago.
• California’s 50th, where indicted Rep. Duncan Hunter is a 7-in-9 favorite against former Obama administration official Ammar Campa-Najjar in a suburban San Diego district that went for Trump by 15 percentage points after going for Romney by 23 percentage points.
• Wisconsin’s 1st, where Speaker Paul Ryan is retiring and his former staffer, Bryan Steil, is a 7-in-9 favorite against union steelworker Randy Bryce in a gerrymandered district Trump won by 10 after Romney (with Ryan as his running mate) won by 4.
• Nebraska’s 2nd, where Rep. Don Bacon is the 4-in-7 favorite against nonprofit executive Kara Eastman in an Omaha-area district that went for Trump by just 2 after going for Romney by 7.
Republicans can also add to their cushion by winning in Minnesota’s 8th, the only Democratic seat in the Lean Republican column and one of just two such districts where Republicans are favorites. The GOP nominee, retired police office Pete Stauber, is a 4-in-5 favorite against former state lawmaker Joe Radinovich in that rural district, which went for Trump by 16 percentage points after going for Obama by 6. (The other Democratic district where the GOP is favored is Pennsylvania’s new 14th, which became more conservative after the state supreme court redrew the state’s map earlier this year.)
Where things could go either way
From there, the GOP will need to keep the momentum going in the toss-up column, where 29 of the 30 races are for Republican seats. A sampling:
• Texas’ 23rd, where Rep. Will Hurd is a 7-in-9 favorite against Air Force vet Gina Ortiz Jones in a San Antonio–area district that went for Clinton by 4 percentage points after going for Romney by 3.
• North Carolina’s 9th, where conservative pastor Mark Harris knocked off Rep. Robert Pittenger in the GOP primary and is now a 5-in-9 favorite against veteran Dan McCready in a Charlotte-area district that went for both Trump and Romney by 12.
• Virginia’s 7th, where Rep. Dave Brat is a 4-in-7 favorite against former CIA operations officer Abigail Spanberger in a suburban and rural Richmond district that went for Trump by 7 after going for Romney by 11.
• Kentucky’s 6th, where Rep. Andy Barr is a 5-in-9 favorite against former fighter pilot and viral star Amy McGrath in a Lexington-area district that went for Trump by 15 and Romney by 14.
• Utah’s 4th, where Rep. Mia Love is a 3-in-8 underdog against Salt Lake County Mayor Ben McAdams in a Salt Lake City–area district that went for Trump by 7 after going for Romney by 37.
• Iowa’s 3rd, where Rep. David Young is a 3-in-10 underdog against Cindy Axne in a Des Moines–area district that went for Trump by 4 percentage points after going for Obama by the same margin.
The sole Democratic toss-up? The open seat for Minnesota’s 1st, where four-time GOP candidate Jim Hagedorn is a 4-in-9 underdog against Army vet Dan Feehan in the rural district that went for Trump by 15 percentage points after going for Obama by 1 percentage point.
Where they’ll need to pull off the upsets
Barring a near-sweep of those races, the GOP will still have some work to do to keep the House. Democrats are the clear favorite in a total of 18 GOP districts; in five of them, Cook doesn’t even give the GOP a chance. In a hypothetical world, then, where Republicans hold on to each and every of the 28 GOP seats that lean their way and win two-thirds of the 30 toss-ups, they’d still need to score a handful of upsets in the group of 13 GOP seats that Lean Democrat. A sampling:
• Kansas’ 3rd, where Rep. Kevin Yoder is a 1-in-7 underdog against attorney and former MMA fighter Sharice Davids in a Kansas City–area district that went for Clinton by 1 percentage point after going for Romney by 10 in 2012.
• Colorado’s 6th, where Rep. Mike Coffman is a 1-in-9 underdog against Army veteran Jason Crow in a suburban Denver district that went for Clinton by 9 percentage points after going for Obama by 5 percentage points.
• Iowa’s 1st, where Rep. Rod Blum is a 1-in-20 underdog against state Rep. Abby Finkenauer in a Cedar Rapids–area district that went for Trump by 4 after going for Obama by 14.
• California’s 49th, where state tax official Diane Harkey is a 1-in-30 underdog against attorney Mike Levin in this San Diego–area district that went for Clinton by 8 percentage points after going for Romney by 7 percentage points.
Unlike in the Senate, there is no single House race of outsize importance, and so there are myriad ways either party can cobble together the 218 seats it needs for a majority. Like Senate Democrats, however, House Republicans are going to need to beat the odds more often than they don’t on Tuesday if they’re going to be celebrating on Wednesday.
Is that probable? By definition, no. Is it possible? By definition, yes.
Correction, Nov. 6, 2018: This article originally misstated that the runoff in Mississippi’s special election would happen in December.
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