Why the GOP’s popular-vote edge hasn’t translated to more House seats

The 2022 election, though, looks like it will buck that trend.

Republicans appear primed to win the narrowest of House majorities — around 220-215 or 219-216 — despite possibly winning a majority of the votes nationwide and edging Democrats by around three or four percentage points.

If they do ultimately win by around three or four points, it would mean Republicans improved on their margin from the 2020 election by around six or seven points, but they were only able to add about 2 percent of seats, as the Cook Political Report’s Dave Wasserman notes.

This has understandably led to some griping and head-scratching among Republicans who wonder how they’re struggling to win the House despite that swing. But it’s worth putting in context.

The first thing to note is that we have incomplete results. The Cook Political Report’s national popular vote tracker currently shows Republicans winning 51.5 percent of House votes to the Democrats’ 47 percent — a gap of 4.5 points. It’s safe to assume Republicans will win the popular vote by a few points, but that margin will continue to narrow as we get more results from blue-leaning states out west, especially California.

The second point is that the popular vote can be deceiving. That’s especially the case in the battle for the Senate, but it’s also true of the House.

The reason: Some districts don’t feature two major-party candidates, and as a result, those races skew the overall numbers. That’s because having no major-party opponent generally means candidates run up a much bigger margin than they otherwise would.

In the 2022 election, there were many more uncontested House districts held by Republicans (14) than by Democrats (3). And there were another 10 districts in which the GOP had no major-party opponents, compared with just three for Democrats.

Thanks to California’s top-two primary system, there are also another six districts in which Democrats have the votes all to themselves, because the two finalists are both Democrats.

So effectively, there are more than 20 districts in which the GOP could run up the score, compared with a dozen for Democrats. They would be able to run up the score less in races with third-party candidates also on the ballot, but it still skews the numbers in the GOP’s favor, to some degree. (A note: Two uncontested districts held by the GOP are in states that don’t tally votes in uncontested races, which somewhat diminishes the GOP’s advantage on this metric.)

Excluding those districts from the popular vote altogether would also be misleading, given they heavily favor the party that’s actually running a candidate and would be good for the GOP. But it’s safe to assume the GOP wouldn’t be leading by quite as much if every district featured a Democrat versus a Republican.

Yet even accounting for that, the 2022 election is unusual. That’s because it appears as though it will be only the second election since 1994 in which Democrats will win a higher percentage of seats than of the two-party popular vote.

If Democrats lose the popular vote by about three points and win 215 seats, they will have won 48.5 percent of the two-party vote and 49.4 percent of the seats — a gap of about one percentage point in their favor. Here’s how that would compare historically:

The only other time that happened since 1994 was 2008, when Democrats turned 55.5 percent of the two-party popular vote into 59 percent of the seats — a gap of 3.6 points in their favor. And it’s no coincidence that election delivered the biggest House majority for either side since the early 1990s; huge popular vote wins tend to lead to even larger majorities, because the winning side sweeps the vast majority of competitive races.

Besides that election, though, Republicans have gained a disproportionate number of House seats in every other election over the last 28 years. The gap was particularly pronounced in 2012, 2014 and 2016, thanks to the GOP’s successful gerrymandering after the 2010 census.

But Republicans again exercised superior control over redistricting following the 2020 census (which probably delivered them the majority). So why didn’t it happen again?

There are probably a number of answers.

One is that it could be a statistical fluke — just Democrats happening to do better than would be expected in the most competitive races. Another possibility: the lackluster GOP candidates in a number of important races, who might have held the party back from making gains more commensurate with their overall edge in the popular vote (i.e., shrinking a likely gain of around 20 seats to one that’s fewer than 10). That would be in line with what happened in the Senate, where Republicans left winnable races (and in that chamber, the majority) on the table by running flawed candidates.

But it’s also worth emphasizing that the gap between the votes Democrats got and the seats they’ll control isn’t wildly out of step with the historical norm. Even in the “Republican Revolution” of 1994, Democrats won more seats than their popular vote share suggested. And if you stretch back earlier than 1994, the results of this election are very much in line with what we would expect from such a popular vote.

Princeton University’s Sam Wang plotted elections dating back 1946 and found that a two-to-four-point Democratic loss on the popular vote would leave the 2022 race in line with what we would expect from the ultimate balance of power:

Regardless, it shows how election results can test our priors. In recent years the conventional wisdom has been that even a small GOP edge on the generic ballot suggests it’s in line for significant gains. And plenty of recent history backs that up.

But there are always exceptions. And this is hardly the only way in which the 2022 election appears exceptional.

This post has been updated with the latest 2022 data and more historical data.