Democrats' Special Election Edge Still Points to a Big Year (Democratic Wave?)

In April, we ran an analysis of how well Democrats were overperforming their 2024 margins in this year's state legislative special elections and what that might tell us about their chances in November. But that analysis came with two caveats: (1) the special election overperformance tends to moderate on the day of the general election and (2) during the 2018 cycle, when Democrats had comparatively high overperformance numbers during that year's specials, the special elections advantage in the final few months before the election came back down to earth, yielding a much lower overperformance margin than the first half of the year. So we wanted to keep an eye on the remaining special elections to see if the same pattern held this year.

2026 Special Elections Show Sustained Democratic Overperformance

Unlike in 2018, Democratic margins in 2026 have held through the end of the special election cycle. In 2018, Democrats overperformed Hillary Clinton's 2016 presidential margin by a median of 14.7 points (33 contested specials) in the Jan-Apr period (a majority of specials typically take place in the first part of the year), but from May-Oct that year, that Democratic advantage shrank to a median of 0.2 points (18 contested specials), bringing their overall 2018 overperformance in special elections to a 5.3 median swing (51 races). That translated into a 3.9-overperformance in the 2018 general elections.

This year, that second-half dip in special election margins did not surface. During the Jan-Apr period, Democrats overperformed Kamala Harris' 2024 margins by 10.4 points (37 contested specials) and sustained that median advantage through the latter half of the year with a 10-point margin (six contested specials). That last number should give us some pause though. In 2018, the May-Oct period saw 18 contested special elections, whereas in 2026 we only have six special election outcomes to work with. That's likely too small a sample size to draw any strong conclusions.

Projecting Special Election Results to November General Elections

But what does this mean for Democrats in November? That's harder to say. Directionally, it's certainly good for Democrats that the special elections overperformance didn't crater as the year went on, but the raw number needs adjusting before it tells us anything about the general election. Historically, a party's special election overperformance should be discounted before applying it to November. Turnout is way different for specials versus the general even if the specials may tell you something about party enthusiasm that year. Based on data from recent election cycles, a reasonable discount is roughly 1.5 to 4 points in November below what the party was seeing in the specials.

The bottom line is that a reasonable projection from the special elections to November in 2026 would have Democrats overperforming the 2024 presidential margins by six to nine points this year, which would net them roughly 424 to 593 state legislative seats. This is close to what professional forecasters project. Currently, our friends at State Navigate project Democrats to net 403 seats.

Historical Context and Potential Seat Gains

That would be significant. In 2018, the party's last wave year, Democrats netted 308 legislative seats, while also picking up 7 governorships and 6 trifectas. Those numbers aren't far from our "What would a Democratic wave election look like?" hypothetical from last week, which would see Democrats gaining six new trifectas in 2027. We're now under a month from Election Day, which leaves us plenty of time to read the tea leaves and adjust projections.

Track Elections and Other Political Activity

Federal and state elections and redistricting can have significant policy and regulatory implications for businesses and organizations. If your organization would like to further track federal and state elections, please contact us.

Frequently Asked Questions