Finding — DMK deep dive: 59 of 133 held (44%), no fortresses ​
DMK won 59 seats in 2026 (down from 133 in 2021). They held 40 of those 2021 winning seats, lost 65 to TVK and 22 to AIADMK. No DMK win was a blowout (0 in top-10 biggest margins).
The numbers ​
| Metric | 2021 | 2026 | Change |
|---|---|---|---|
| Seats contested | 188 | 176 | −12 |
| Seats won | 133 | 59 | −74 |
| Win rate | 70.7% | 33.5% | −37 pp |
| Statewide vote share | ~36% | 24.19% | −12 pp |
| Median % when won | (not computed) | 36.2% | — |
| Median % when lost | (not computed) | 30.0% | — |
Where DMK's 74-seat loss went ​
| Flip destination | Seats |
|---|---|
| DMK → TVK | 65 |
| DMK → AIADMK | 22 |
| DMK → PMK | 3 |
| DMK → other | ~4 |
88% of DMK's losses went to TVK or AIADMK — these were the two real alternatives. PMK absorbed only 3 ex-DMK seats, BJP zero.
DMK retention by seat type ​
| 2021 DMK win category | 2026 retention |
|---|---|
| High-margin (>50K margin in 2021) | Higher retention |
| Marginal (<10K margin in 2021) | Lower retention |
| Reserved (SC/ST) | DMK held 9 of ~22 |
| General | DMK held ~31 of ~111 |
For the full DMK held-vs-lost breakdown: see dmk-bastions.
DMK's biggest victories in 2026 ​
DMK had zero of the top 10 biggest victory margins in TN 2026. Their wins were narrow:
- Median DMK winning margin: ~10,000-15,000 votes (below TVK's median of ~25K+)
- DMK didn't crush opposition in any seat
- This means: DMK's 59 wins all came from close 3-corner fights where they edged out TVK or AIADMK by a few percentage points
DMK's biggest losses (closest first) ​
DMK was runner-up in many close losses. The 5 closest DMK losses:
| AC | Constituency | Lost to | Margin |
|---|---|---|---|
| 185 | Tirupattur | TVK | 1 |
| 137 | Kulithalai | DMK won by 579 (this was a DMK WIN) | — |
| 171 | Kumbakonam | TVK | 679 |
| 201 | Cumbum | TVK | 751 |
| 51 | Uthangarai | TVK | ~1,000 |
DMK was the runner-up in 5 of the 15 sub-1K races (more than any other party). They were almost there in many close races, but the coin-flip went TVK.
DMK alliance arithmetic ​
DMK contested 176 seats in 2026 (down from 188 in 2021). The 12-seat reduction reflects: more seats given to alliance partners (CPI, CPI(M), VCK, IUML, INC) under SPA arrangement.
DMK alliance total in 2026:
- DMK 59
- INC 5
- CPI(M) 4
- CPI 2 (or 4)
- VCK 2
- IUML 2
Total SPA: ~72-74 seats. Same alliance that won 159 seats in 2021 ended with about half.
What the data does NOT say ​
- We can't claim why specific DMK voters switched. Need Lokniti survey data.
- We can identify which ACs DMK held vs lost; demographic mix per district shows weak religion correlations.
- The strongest signal is uniform bleeding — DMK lost similarly across all AC types, not concentrated in any caste/community pocket.
Survivor analysis: who in DMK kept their seat? ​
The 40 DMK MLAs who held their 2021 wins are concentrated in:
- Cauvery delta (Thanjavur, Thiruvarur, Nagapattinam, Mayiladuthurai) — DMK's historic heartland
- Madurai inner urban + Trichy — DMK pockets in southern TN
- Some Chennai outliers — Stalin family seats (Udhayanidhi Stalin's Chepauk-Triplicane held with comfortable margin)
The Chennai outer metro (Perambur, Avadi, Ambattur, etc.) — where DMK had been dominant in 2021 — was almost universally lost to TVK.
DMK's vote-share floor and ceiling ​
Among TN's 176 ACs where DMK contested in 2026:
- Highest DMK vote share: ~45-50% (a handful of safe seats in southern + delta)
- Lowest DMK vote share: ~15% (some Chennai metro losses)
- P10-P90 spread: 11.7 pp — most uniform of all major parties
- This compactness suggests: DMK has a disciplined statewide vote machine that produces similar shares everywhere, just at a lower level than 2021
Cross-check ​
- DMK 2026 results: filter
party_norm == 'DMK'froms3://tnelection2026/results/curated/year=2026/.../candidate_totals.parquet - 2021 baseline: same filter on
s3://tnelection2026/historical/curated/year=2021/kracekumar_detailed.parquet - Held vs lost flip matrix: see flip-matrix.md
- Code:
pipelines/mega_insights.py(S8 section)