Uh-oh. Think partisanship has been bad in recent U.S. political history? It might be about to get much worse.
Over at the Crystal Ball, Kyle Kondik looks at Senate elections — not just in 2018, but in 2020 and 2022 as well. The basic story is that after Republicans have excellent opportunities in 2018, they'll still have a pretty good map in the 2020 elections. It's the 2022 elections that will finally give Democrats plenty of excellent targets.
That's all correct, but it's easy to overdo it. Right now, the Cook Report has five toss-up Senate seats for 2018, three currently held by Democrats and two by Republicans. Democrats have several other seats they hold that are rated as "leaning" or "likely" their way, so if 2018 winds up a good Republican year, there's still a possibility of big Republican gains. But with an unpopular Republican president, the odds are it will be a good year for Democrats, which probably translates into a break-even year plus or minus a couple of seats. And then if Donald Trump loses in 2020, Democrats will be well within range of reaching at least 50, and therefore organizing the Senate.
Meanwhile, Democrats are likely to make at least some gains in 2018 in the House — after all, Republicans have more exposure there because they will be defending an unusually large Republican majority. That's easily visible in the Cook Report House ratings, which count 56 vulnerable Republican seats and only 19 vulnerable Democratic seats. Again, it's always possible Trump will surge and wipe out most of those potential Democratic gains. But if he remains unpopular, Democrats will come close or even attain a House majority in the 2018 elections — and if a Democrat is elected president in 2020, his or her coattails should be long enough to mean a Democratic House in 2021.
Now, the huge "if" is the 2020 presidential election. It's way too early to make even a wild guess about the outcome. Trump's awful polling numbers have already begun to lock in problems for his party in the midterm elections, but there's more than enough time for him to bounce back and win easily in 2020. Trump's a little bit south of 40% approval right now. That's lower than Barack Obama ever reached, and lower than Bill Clinton would hit after October 1993; Clinton's low point in the mid-30s was already in the rear-view mirror by this point of his presidency. But Harry Truman was in the low 30s during his second year in the White House, and Ronald Reagan bottomed out at around 35% approval in early 1983.