The president’s party almost always suffers in the House

Midterms are less than a year away so it’s time to look back at the record. 

In the House, the president’s party has lost seats in all but four midterms since 1862, and one of those, 1902, was a year the House expanded so the Republican gains fell short of Democratic gains that year. After 1934 it wasn’t until 1998 that the president’s party gained seats, then the rare event repeated in 2002. Not since.

This regularity over 160 years is hard to attribute to the circumstances of the moment. Likewise the hope that “this year will be different” has been a forlorn one. The size of the seat loss, on the other hand, has varied considerably and is correlated with presidential approval (Clinton in 1998 and Bush in 2002 were unusually popular, as was Roosevelt in 1934) and the state of the economy. Popular presidents lose fewer seats, unpopular ones more. Good times go with smaller losses, bad times with greater losses. 

In 2026 we will have the unprecedented circumstance of a large number of mid-decade redistricting decisions as the parties battle to see who can gerrymander the most seats to their advantage. That landscape is still being painted.

In the Senate the pattern of losses are much less dependable than in the House. The president’s party usually loses seats, and the gains have been small since the 1940s. The vagaries of which seats are up and how many for each party adds uncertainty to the Senate picture. And, of course, prior to 1913 the Senate was not elected by popular vote.

In the House, the second midterm for a president produces barely grater losses than the first midterm (an average of 28.9 in the second, versus 24.9 in the first.) There isn’t a “six-year itch” on the House side. The Senate has been a different matter, with second midterm losses averaging 6 seats rather than 2 in the first midterm (since 1946.) One plausible explanation for the Senate is that the 6th year is the reelection of a Senate class elected with the president for his first term. To the extent a winning first term president brings along some partisan companions, they run without his coattails 6 years later. The table shows the seat changes and the averages since 1946.

Next year there will be inevitable discussion of whether 2026 is Trump’s second midterm. Obviously it is in one sense. But for the Senate, this will be the class elected with Joe Biden in 2020, not the class elected with Trump in 2016. This group had mild pro-Democratic national forces either helping or hurting them in 2020. Given this difference in the election cycle, the average 6 seat loss may not be as good a representation of expectations for Senate seats in 2026.