The House of Representatives is almost certain to remain in Republican control after Tuesday’s elections. The Cook Political Report is calling for Republicans to pick up a net of six to 12 seats, with more gains possible. The Rothenberg Political Report is calling for Republicans to pick up a net of five to 12 seats, which would give Republicans about 240 seats in the next Congress.
These results fall in line with what we’d expect given the national political environment. But if the GOP were more popular, bigger gains would be likely.
According to the latest Huffington Post Pollster aggregate, Republicans lead on the national generic ballot by 2.3 percentage points (Real Clear Politics has about the same). We can get a good idea of how this lead translates into seat gains using a vote-to-seat curve. I created one last year that took into account the most recent round of redistricting.
Any vote-seat curve is rough because one side can win a bunch of races by small margins, making the aggregate look tight while the seat count is more lopsided. Still, the curve here seems to be doing a good job picking up what the district-level analyses are seeing. According to the curve, Democrats will have about 191 seats in the new House given a 2.3 percentage-point deficit on the generic ballot. That would be a net loss for Democrats of eight seats. That’s in the middle of the Cook and Rothenberg ranges.
What’s driving this small Republican gain? Individual district factors matter, but so does the fact that it’s a midterm election, which are historically bad for the president’s party. Attitudes toward the president also matter. Both those factors favor Republicans. But a few months ago, I illustrated how congressional approval influences the national House vote when one party controls Congress and the other controls the White House. Voters recognize that both parties have a stake in the government.
President Obama has a 42.4 percent approval rating, and Congress has a 12.4 percent approval rating. Given those numbers, we’d expect Republicans to win the national House vote by 2 percentage points — very close to what the generic ballot shows.
A Republican gain of five to 12 seats is significantly less than one would expect using presidential approval ratings alone as a predictor. If voters cared only about Obama’s performance, we’d expect a much more lopsided result: A Democratic loss of about 25 seats. That seems unlikely. Part of the reason that gains will be kept down is that, at 12.4 percent, this is the lowest congressional approval rating going into a midterm election since the question was first asked in 1974.
Overall, the House is all but determined. It’s falling right along the lines that we thought it would given the factors that normally accurately forecast House elections. Republicans are set to gain because it’s a midterm year and the president is unpopular, but they probably aren’t picking up as much as ground as they would if Congress were more popular.