Decoding Bengal SIR data: Of 123 margins, 49 in closer focus | India News
BJP Mighty, winning 207 seats, surpassing most expectations TMC 80 has been humbled, and other groups have been reduced to mere footnotes.The anti-incumbency was so intense that it probably fueled much of the uneasiness and anger around the SIR, which the TMC sought to gain, many pundits believe. Some had earlier argued that the deletion was done in a politically motivated manner to tilt the odds in the BJP’s favor, particularly pointing to the “logical inconsistency” factor introduced late in the SIR process.Here, we decode the data based on different thresholds.To understand the potential impact of SIR, the most obvious starting point is to examine seats where the voter erasure margin was greater than the seat won.This analysis uses the Saber Institute’s constituency-wise deletion calculations, mapped to 2026 result-margin data. Net delete here means deletion for reasons other than death. The net-deletion table covers 294 assembly constituencies and adds up to 66,62,010 deletions.And here comes the first big number.In 123 of Bengal’s 293 declared seats, the net removal was greater than the margin of victory. BJP won 83 of these seats, TMC 38 and Congress 2 In 83 of the 123 constituencies, the BJP has roughly two-thirds, broadly its overall electoral dominance in the same region.There is a second, sharper layer. Removing the supplementary from the supplementary/judgment level, the margin of victory exceeded 49 seats. It refers to under-judgment voters whose names are eventually deleted. At final count, 27.16 lakh out of nearly 60 lakh under-judgment names have been deleted. Mapped constituency-wise, the BJP won 26 of these 49 seats, the TMC 21 and the Congress 2.For clarity, we are using the term stress in a narrow mathematical sense. A seat is counted as a deletion pressure seat if the number of deletions is greater than the margin of victory. So if a constituency is won by 5,000 votes and 12,000 net removed, that seat enters the pressure list because the removal was by more than double the margin.
This does not mean that the results will change. This means that the number of deletions was large enough to be a selective factor compared to the margin alone.All 49 of these supplementary-deletion stress sites were already inside the larger 123-site net-deletion stress universe.
These numbers are important because they prevent the debate from becoming vague. In 65 seats, the net removal was not only larger than the margin; It was more than double the margin. In 20 seats it was more than five times the margin. Even by the narrow complement-deletion test, 23 seats exceeded the 2x mark and 10 seats exceeded the 5x mark.This is not a clerical footnote.Take Rajarhat New Town. BJP won by just 316 votes. Net deleted 50,274. Only supplementary removals were 24,132. By supplemental testing, removal was by a 76-fold margin; By the net-wipe test, it was more than 159 times the margin.In Satgachiya, the BJP’s margin was 401, while the net wipe was 17,783 and the supplementary wipe was 8,785. In Kashipur-Belgachia, the BJP won by 1,651, with a net loss of 39,278.This number does not say the results will change. They said the number of deletions was too large to ignore.But this is where the story becomes more interesting than partisan talk. High deletion pressure does not always mean BJP wins.See Samerganj. TMC won by 7,587 votes. Congress in second place. Net deleted 83,662. Supplemental removals alone were 74,775, nearly 10 times the margin. If the pressure to wipe out automatically translates into BJP gains, Samserganj will not look like this.The sharp political question, then, is not just where erasures cross the margins. Whether there is a sharp division of votes in this seat too. Has the BJP grown exponentially? Did the TMC fall sharply? Does the removal-margin map overlap with the political swing map?The clean benchmark comes from the 129 seats that went directly from the TMC in 2021 to the BJP in 2026. In these seats, the BJP’s average vote-share gain was 10.63 percentage points on an adjusted basis, while the TMC’s average decline was 8.90 points. The mean two-way churn was 19.53 points.The strongest churn signal comes from the overlap of the top 50 BJP-gain seats and the top 50 TMC-drop seats, both measured in percentage-point terms. Both lists have thirty-five seats. Of this, the BJP gained an average of 15.93 points, while the TMC lost 12.35 points. This is the real churning zone, where the rise of the BJP and the fall of the TMC have coincided.This is important because the 123 removal-margin seats are not of a political type.
Some BJP-converted constituencies, where deletion pressure and churning went hand in hand. Some TMC-lost seats where the beneficiary was not always the BJP. Some arithmetic-only stress seats, where the deletion gap crossed but the vote-share movement was not dramatic.Bhavanipur is a good example of the first type. It is not part of the 49-seat complement-deletion stress list. There was a smaller than supplemental removal margin. But the wider net removal was 2.66 times the margin. At the same time, BJP’s vote share increased by 17.86 percentage points, while TMC’s decreased by 15.52 points.So Bhavanipur is not a trial and erasure story. It’s a net-wipe-plus-churn story.Jadavpur also tells a similar story. Net removal was 1.25 times margin. Complement removal was small. But the BJP’s vote share increased by 21.29 points, while the TMC lost 11.58 points. Jadavpur is not at the center of complementation, but it is part of a wide removal-margin and churn map.Nandigram, however, is different. It technically falls within the net-wiping stress zone, but only just. BJP won by 9,665 votes. Net deletions were 9,891, just 226 more than the margin. Supplemental removal did not exceed the margin. BJP’s vote-share gain was only 1.88 points. TMC’s decline was 1.09 points.The 49 supplementary-stress constituencies also have a diverse political spectrum.
A few clear BJP-origin seats. Jangipur, for example, showed a three-fold margin over supplementary removal, with the BJP gaining 20.73 points and the TMC losing 30.88 points. Rajarhat New Town, Kashipur-Belgachia, Manikchak and Monteswar also fall into this strong bucket: the relegation margin has crossed, the BJP has risen sharply, and the TMC has fallen sharply.But another set tells a different story. Farakka, Raninagar, Lalgola, Raghunathganj, Mothabari, Suti and Samserganj saw the TMC erode due to high deletion pressure, but the beneficiary was not always the BJP. In parts of Murshidabad and Malda, the Congress and local contest structures are important. Lower Trinamool votes do not always translate into increased BJP votes.Then there is a third bucket. Raina, Pandaveshwar and Jangipara had higher wipe-to-margin ratios, but weak BJP-TMC churn. Pandavesvara is particularly useful as a warning. The BJP won and the supplementary elimination was more than four times the margin, but the TMC’s vote share actually increased by 0.29 points. It cannot be called an anti-trimool churning seat.In a smaller set, particularly in Kolkata and urban-adjacent regions, margin stress overlapped with a sharp rise of the BJP and a sharp decline of the TMC.Hence, there is no definitive way to say that the constituencies most affected by SIR have disproportionately helped a particular political party. At a micro level it largely reflects the existing ground situation of a given constituency. SIR had “special” in its name, but the result didn’t stick out as a statistical sore thumb. What stood out was the margin math it left behind.
