Four-point national misses: 2026 midterm polls underestimated democratic support
The scale of the miss
National polls underestimated Democratic strength by around four percentage points. In key Senate races, the average miss was larger, at five points, compared with about 3.5 points across all Senate races.
The error was similar in size to recent polling misses in presidential elections. In 2020, national polls understated Republican support by about four points, and in 2016 by three.
Some pollsters differed
The pattern was not shared by every polling organization. The New York Times/Siena Poll did not systematically underestimate Democrats. AtlasIntel and Survey 160 were also among the pollsters that did not show a systematic underestimate. The overall results therefore concealed differences among pollsters.
Which races were examined
The analysis covered selected states with at least five polls during the final three weeks before Election Day. Alaska was excluded because its results were not finalized.
Key points
- National polls understated Democratic strength by around four percentage points.
- The average miss in key Senate races was five points.
- The error was comparable in size to polling misses in 2016 and 2020.
- The New York Times/Siena Poll, AtlasIntel and Survey 160 did not systematically underestimate Democrats.