The Truth Hurts! · 7 Levels Deep
160 years of midterms: what history says about tonight
Since 1858, the president's party has lost ground in the House in 37 of 41 midterm elections. It happens to Democrats and Republicans alike.
Every midterm since 1858
Tap or hover over any bar to see percentage points and actual seats.
Why percentages instead of seats?
A 30-seat loss in 1870 isn't the same as a 30-seat loss today. Back then the House had about 240 members. Today it has 435. The House grew as new states joined and the population climbed, until Congress capped it at 435 in 1913. The Senate grew too, adding two senators with each new state, until it reached 100 in 1959.
So this chart measures each loss as a share of the chamber: how much of Congress the president's party lost, not just how many seats.
The pizza problem: 1902
In 1902, Theodore Roosevelt's Republicans gained 7 House seats, yet their share of the House fell 2.9 points. How? The House grew after the 1900 census.
| Republicans | Democrats | Republican share | |
|---|---|---|---|
| After 1900 | 200 | 151 | 57.0% |
| After 1902 | 207 | 176 | 54.0% |
Think of a pizza. You have 4 of 8 slices: half the pizza. Then the pizza grows to 12 slices and you get 5. You gained a slice, but you went from half the pizza to about 42%. You gained a slice and still lost ground.
The reverse happened in 1878: Rutherford Hayes's Republicans lost 4 seats but gained 1.6 points of the House.
"Points" vs. "percent"
A drop of 2.9 percentage points means the party's share went from 57.0% to 54.0% of the House: 2.9% of the whole chamber. That's what this chart shows.
The exceptions
Only four midterms bucked the pattern in the House: 1878 (Hayes), 1934 (Franklin Roosevelt, during the New Deal), 1998 (Clinton) and 2002 (George W. Bush, after 9/11).
Tonight
With a Republican in the White House, 160 years of history points to Democratic gains. If Republicans hold their ground, they'll have beaten long odds. Either way, the 2026 bar goes at the top of the chart once the results are in. Close races can take days or weeks to call, so check back.
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Sources and method
- Seat counts: House of Representatives and Senate historical records, as compiled by USAFacts (composition of Congress after each election, 1856–2024).
- Midterms only: presidential election years are excluded. Andrew Johnson's 1866 midterm is excluded because his party affiliation was ambiguous.
- Shares count only Democratic and Republican seats; third-party members and vacancies are left out.
- Change is measured from the composition after the previous election to the composition after the midterm.
Published by 7 Levels Deep. Last updated November 3, 2026.