Following the 2018 midterm elections, Democrats, despite flipping at least 40 House seats and wresting Congress’ lower chamber from Republican hands, actually ended up losing a net of two Senate seats. When the 116th Congress is sworn in next month, the upper chamber will be split 53–47 in Republicans’ favor (including the two independent senators who caucus with the Democrats).
As the last election shows, Senate races are idiosyncratic and don’t always align with shifts in the national mood from one cycle to the next. That’s partly due to the fact that United States senators serve six-year terms, meaning only one-third of the Senate is up for election at any one time. It’s also due to the unrepresentative nature of Senate apportionment; every state, no matter the size, has two senators. This gives small-state voters — who are currently more likely to support Republican candidates — greater voting power.
Because the median state is significantly more Republican-leaning than the nation as a whole, it’s important for Democrats to take special care in preparing for Senate elections. In the current political landscape, they’re the underdogs — and they know it.
In 2020, Democrats must win a net of three seats and the vice presidency, or four seats without the vice presidency, to assume control of the Senate. That’s a tough objective, but not impossible. To maximize their chances, Democrats should target the following seven Republican-held seats, listed in order from most likely to least likely to turn blue.
For each seat, I’ve included the name of the current Republican incumbent, the incumbent’s previous margin of victory and the respective state margin in the 2016 presidential election.
I decided to include the most recent presidential results, as opposed to the state’s latest Senate election results, for two reasons: First, every state participated in the 2016 presidential election, whereas not every state held its last Senate election in the same year. This keeps the data uniform. Second, President Donald Trump will likely be on the top of the ticket once again in 2020, and there is a decently high correlation between Senate election results and state-level presidential election results when both contests are on the same ballot.
Incumbent: Sen. Cory Gardner
2014 Senate Margin: (R) +2.5
2016 Presidential Margin: (D) +4.9
Sen. Cory Gardner is the most vulnerable Republican incumbent in the Senate. He eked out a victory in 2014 — a very strong year for Republicans across the board — and his state has only become more Democratic leaning since he assumed office. If Democrats can flip any Senate seat in 2020, they can surely flip Colorado.
Incumbent: Sen. Susan Collins
2014 Senate Margin: (R) +37
2016 Presidential Margin: (D) +2.9
This one is controversial; as you can tell by Sen. Susan Collins’ 2014 blowout, she has been quite popular in her state in the past. But part of Collins’ popularity was driven by her image of being a moderate Republican in a purple state. That perception was hurt in October when she cast the deciding vote in favor of Supreme Court Justice Brett Kavanaugh’s confirmation — a highly controversial process in which several accusations of sexual assault were levied against the judge (which he denied).
This race is likely to draw a strong Democratic challenger. What’s more, whomever the Democrats nominate will start the campaign with a huge advantage: a $3 million fund raised in the wake of Collins’ vote to confirm Kavanaugh.
2016 Senate Margin: (R) +12.9
2016 Presidential Margin: (R) +3.5
Former Republican Sen. John McCain won the last election for this seat in 2016. McCain died in 2018, leading to the appointment of another Republican, Sen. Jon Kyl, to fill the seat until a special election in 2020. Kyl has said he will not run for election in 2020, leaving the seat open.
What’s more, Arizona seems to have taken a blue turn in recent years — potentially due to President Trump’s abrasive rhetoric against immigrants and communities of color. In 2018, Arizona elected Kyrsten Sinema to fill the seat vacated by retiring Republican Sen. Jeff Flake. In 2020, Democrats might secure the other of Arizona’s two Senate seats, especially if the same Republican candidate returns to run again.
4. North Carolina
Incumbent: Sen. Thom Tillis
2014 Senate Margin: (R) +1.7
2016 Presidential Margin: (R) +3.6
Some may have put this race higher on this list, but North Carolina has remained stubbornly supportive of Republican candidates in various races. Nonetheless, Sen. Thom Tillis has his work cut out for him to gain re-election in a state that, when Trump was last on the ballot, narrowly elected a Democratic governor.
Incumbent: Sen. Joni Ernst
2014 Senate Margin: (R) +8.5
2016 Presidential Margin: (R) +9.4
Iowa is a tricky state to predict; in the 2018 midterms, Democrats won three of Iowa’s four House seats, but lost the governor’s race to a Republican incumbent. However, that was without Trump on the ballot, and Iowa — much like its southern neighbor, Missouri — has caught a bad case of Trump Fever, supporting the president to a much higher degree than your average state. This one is the shortest of long shots for the Democrats, likely to come down to how Iowans feel about four more years of Trumpian politics.
Incumbent: Sen. John Cornyn
2014 Senate Margin: (R) +27.2
2016 Presidential Margin: (R) +9
Texas is in some ways the reverse image of Iowa, the latter being a swing state with a special love for Trump while the former is more of a red state with a bit of Trump skepticism. In 2018, Democratic Senate candidate Beto O’Rourke came within 3 points of ousting incumbent Republican Sen. Ted Cruz, but that was a remarkable outlier.
Democrats could have a chance here if O’Rourke returns for a second shot at the Senate, or if the presidential election brings out enough left-leaning voters in the state’s liberal hubs of Austin, El Paso, Houston and Dallas. In other words: Keep your eye on this race, but don’t expect as strong of a performance for the Democratic candidate as we saw in 2018.
Incumbent: Sen. David Perdue
2014 Senate Margin: (R) +7.9
2016 Presidential Margin: (R) +5.1
By the top-line numbers, you might think Georgia would be an easier target for Democrats. Unfortunately for them, the state’s electorate tends to be relatively inelastic — meaning Georgians rarely switch from voting for one party’s candidates to those of the other party between elections.
If Democrats win in Georgia, they’ve likely already clenched the Senate by flipping several of the other states listed above. ■