When a state legislator resigns, dies, or is removed from office, a special election fills the vacancy. These off-cycle races happen throughout the year and often fly under the radar, but they can shift the balance of power in closely divided chambers and provide early signals about the political environment heading into November.
This page does three things. It tracks every 2026 special election; it measures the swing in contested specials (how Democrats are running relative to their 2024 presidential baseline) against the 2018 precedent; and it translates that swing into a November expectation by discounting it the way past midterms did.
Race-by-Race Tracker
Every 2026 state legislative special election, including uncontested races and same-party runoffs that don't factor into the swing analysis below. Click the section to open the full list; click any row in the list to expand the race card.
2026 Special Elections
| District | Date | Status | Winner | Margin | 2024 Pres |
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Swing Analysis: What These Specials Signal
Across 42 contested 2026 legislative special elections, Democrats are running a median of 10.4 points ahead of their 2024 presidential baseline, and 12.6 points ahead weighted by turnout. The more telling read is how that advantage moved through the year, measured against the same stretch of the 2018 blue-wave cycle, when an early surge faded badly before November:
Did the Democratic Special-Election Advantage Hold After April? 2018 vs. 2026
Median Democratic overperformance of the prior presidential margin in contested state legislative special elections, January–April vs. May–October. Labels show the number of races in each period.
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How We Measure the Swing
For each contested special election where both a Democratic and Republican candidate appeared on the ballot, we compare the result to the 2024 presidential margin in that same district. The difference is the "swing": how much better or worse Democrats performed relative to the presidential baseline. We use the median swing as our primary metric (rather than the mean) because it is resistant to outliers. Individual special elections can produce extreme swings due to candidate quality, local issues, or unusual turnout patterns; the median captures the central tendency without letting any single race distort the picture. For reference, Bolts Magazine found a similar D+13 overperformance in their analysis of 2025 specials.
2026 Special Election Results vs. 2024 Presidential Baseline
Each dot is a 2026 special election. The diagonal line represents no swing (special result = presidential baseline). Dots above the line indicate Democratic overperformance. Gold rings mark seats that changed party.
2026 Special Elections: Democratic Swing by Race
Each bar shows how much Democrats over- or underperformed the 2024 presidential margin. Positive = D overperformance, negative = R overperformance. Gold outlines and "(flip)" mark seats that changed party.
Seats Flipped So Far in 2026
The overperformance isn't just theoretical. Democrats have flipped — state legislative seats from Republican to Democratic control in 2026 special elections, while Republicans have flipped none. These are the races where the swing translated into an actual change in party control:
The 2018 Precedent
The 2018 cycle is the closest precedent for a midterm under a Republican president. That year, Democrats gained 308 state legislative seats and flipped 6 chambers. The specials pointed in the right direction, but the swing changed a lot over the course of the year:
- January through April 2018: D+14.7 median swing (33 races). The early signal was intense, even stronger than what we see in 2026.
- May through October 2018: D+0.2 median swing (18 races). The swing moderated dramatically as the general election approached; only 10 of 18 races showed Democratic overperformance.
- All pre-November 2018: D+5.3 median swing (51 races).
- November 2018: Democrats ran D+3.9 ahead of the 2016 presidential margin in contested legislative races.
2026 broke from that pattern: its May–October specials held at D+10.0, but on only 6 contested races, so the post-April test is thin. Specials held on the same day as the November general election are excluded from all analyses because they have fundamentally different turnout dynamics.
Cycle Comparison: 2018 vs. 2026 Special Election Swings
Each dot is a special election. 2018 pre-November races (▲) compared to 2016 presidential margins; 2026 races (●) compared to 2024 presidential margins. Gold rings mark seats that changed party in either cycle.
Cumulative Swing Through the Cycle: 2026 vs. 2018
Running turnout-weighted average swing as each cycle's special elections occurred, January through the fall. Each step is one special; hover any point for the race behind it. The 2018 line (dashed) ends at that cycle's November general.
From Specials to November
Special elections have historically run ahead of November. To turn this year's special-election swing into a November expectation, we line up the specials in recent midterms against what happened in that November's state legislative generals, on the same presidential baseline, and apply the difference to 2026.
The full comparison
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How special elections compared with November
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A discounted projection for 2026
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November figures: median swing in contested single-member state legislative general elections (exactly one Democrat and one Republican) against the prior presidential margin, on the district lines in effect for that election. Special elections held before a mid-decade map took effect are measured on the old lines. Projection uses the same uniform-swing method as the scenario explorer below.
How the projection compares with past waves
| Metric | 2010 (R wave) | 2018 (D wave) | 2026 Projection* |
|---|---|---|---|
| Net seat change | R+720 | D+308 | — |
| Chambers flipped | 20 to R | 6 to D | — |
| Trifecta changes | R gained 11 trifectas (9 → 20) | D gained 6 trifectas (8 → 14) | — |
| Context | Tea Party backlash to ACA + Obama; redistricting year gave Rs map-drawing power for a decade | Anti-Trump backlash; suburban shift; highest midterm turnout in decades | Anti-Trump second-term backlash; tariff/DOGE disruption; special elections running D+10.4 |
*2026 column is the discounted projection range above, based on uniform swing, not actual results. Alaska's coalition-run chambers are excluded from chamber counts.
Upper bound: what if the undiscounted D+10.4 swing held through November?
No recent midterm has matched its special elections in November, so this is a ceiling, not an expectation. Applying the full special-election median to every seat on the ballot:
Explore Different Scenarios
Use the slider below to explore how different swing levels would affect chamber control across all 99 state legislatures. The slider defaults to the undiscounted median special election swing; the discounted range from the section above is D+6 to D+9. Adjust it to model different scenarios.
The calculator works by taking each district's 2024 presidential margin and shifting it by the selected amount. A district at R+2 with a D+3 swing becomes D+1, and is projected to elect a Democrat. Seats not up for election in 2026 are held at their current party. The +/- numbers show how the projection compares to today's actual chamber control. For full methodology and limitations, see the standalone Swing Calculator page.
Open the full Swing Calculator →
Full Analyzed Results — 2026
| Date | State | District | Winner | Special Margin | 2024 Pres | Swing | Turnout |
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Full Analyzed Results — 2018 (historical baseline)
| Date | State | District | Winner | Special Margin | 2016 Pres | Swing | Period |
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Methodology
For each contested 2026 special election where both a Democratic and Republican candidate appeared on the ballot, we calculate the margin as D% minus R% of total votes cast (not two-party share). We use the same total-vote-share method for the 2024 presidential baseline, so both sides of the comparison are measured identically. This matters in races with significant third-party candidates: in the MA 1st Middlesex special, for example, an Independent candidate took 18.9% of the vote, which would produce an 8-point difference between total-vote and two-party margins.
The swing is the difference: special election margin minus presidential margin. A positive swing means Democrats overperformed the presidential baseline; a negative swing means Republicans overperformed.
Excluded races: Uncontested specials (only one major party candidate), races with no declared winner (runoffs pending), races where one party received zero votes, and elections canceled due to being uncontested. When a jungle primary produced a runoff, only the runoff result is used.
Limitations and caveats:
- Sample size. With 37 contested 2026 specials analyzed so far, the sample is growing but still limited. A single unusual race can meaningfully shift the median. Only a handful of 2026 specials fell after April, so the post-April read in particular rests on very few races.
- Turnout differences. Special election turnout is typically 10-20% of a general election. The electorate that shows up for a February special in a single district is not representative of the November electorate. Higher-engagement voters (who tend to be older and more partisan) are overrepresented.
- Candidate quality. Special elections often feature unusual candidate matchups. A particularly strong or weak candidate can produce a swing that reflects local dynamics, not the national environment.
- Geographic bias. Specials happen where vacancies occur, which is not a random sample of districts. Some states and regions are overrepresented.
- Uniform swing is a simplification. Applying a single national swing number to every district ignores redistricting effects, incumbency advantages, campaign spending, and local issues. Real elections do not move uniformly.
- A short history. The specials-to-November discount comes from two midterms (2018 and 2022). Earlier cycles are not usable: the database holds too few contested specials before 2017 to measure them. Two data points describe a range, not a reliable model.
With these caveats in mind, the special election swing is best understood as a thermometer reading of the current political environment, not a forecast, and the discounted projection as an illustration of what history suggests. The direction matters more than the precise number.
Why the overperformance? Turnout data from Ballotpedia offers a key insight: in recent specials, Democratic voters retained 38% of their general election turnout, while Republican voters retained only 28%. This 10-point enthusiasm gap is the primary driver of Democratic overperformance. Whether that gap persists through November, when turnout is vastly higher and less partisan, is the central question this analysis cannot answer.
Sources and further reading: Cook Political Report · Bolts Magazine · Ballotpedia · The Conversation · NBC News