The conventional wisdom is that 2018 will be a good year for the Democrats given how unpopular President Trump is, but in actuality the Democrats will be facing an uphill battle because the map is heavily skewed against them.
Dave Wasserman of the Cook Political Report highlights this stunning fact in a FiveThirtyEight piece: even if the Democrats were to win every House seat in districts that Hillary Clinton won in November as well as every Senate seat in states that Clinton won, they still wouldn't have a majority in either House of Congress.
In fact, they would still lose five seats in the Senate.
The Democrats are in a precarious position of having to defend a whopping 25 seats in the Senate while the GOP only has to defend nine. With that kind of map, the Republicans don't even need to win a swing state in order to maintain their majority, per Wasserman.
What also works in the GOP's favor is that the demographic shift of Democrat voters to urban areas and GOP voters to rural areas:
In the last few decades, Democrats have expanded their advantages in California and New York — states with huge urban centers that combined to give Clinton a 6 million vote edge, more than twice her national margin. But those two states elect only 4 percent of the Senate. Meanwhile, Republicans have made huge advances in small rural states — think Arkansas, North and South Dakota, Iowa, Louisiana, Montana and West Virginia — that wield disproportionate power in the upper chamber compared to their populations.
According to Wasserman, "Democrats hold six seats in the 26 more-Republican-than-average states, and all six are at risk in 2018."
It's certainly not impossible for the Democrats to win in 2018, as the 2006 map favored the GOP and yet they lost control of Congress to Democrats, but the Democrats were able to use the Iraq War and Hurricane Katrina as political bludgeons against the Republicans; no such bludgeons exist quite yet against Trump.
On Larry Sabato's Crystal Ball, Republicans are projected to have 51 seats following the 2018 midterms and the Democrats are projected to have 45, with four seats rated as toss-ups. However, Crystal Ball Managing Editor Kyle Kondick noted that 187 House Republican seats and 173 Democratic seats are considered "safe" and there are a large number of "Likely Republican" seats, but it's difficult to determine how many of those are actually vulnerable in 2018.
The Democrats do have one thing going for them – FiveThirtyEight has Democrats winning the generic ballot over Republicans by a margin of 47.4% to 37.2% for Congress, but even that might not be enough for the Democrats to regain control of Congress in 2018.