West Bengal Assembly Elections 2026 | How razor-thin margins, SIR deletions could decide who forms govt

More than 90.83 lakh names have been deleted across West Bengal till April 7, nearly 11.85% of the electorate identified last October.

Kolkata: West Bengal's 2026 election may be decided not by the arithmetic of 294 seats that dominate campaign speeches, but by around 65-70 constituencies where victory and defeat are separated by little more than a few booths and where the Special Intensive Revision (SIR) of electoral rolls has suddenly redrawn the battlefield.

Crucial among those are seats such as Nandigram to Bhabanipur, and regions like the Matua belt of North 24 Parganas and the minority-heavy stretches of Murshidabad and Malda, where the assembly-wise lead in the 2024 Lok Sabha polls was often no more than 8,000 to 15,000 votes. Several MLAs had scraped through in 2021 in these areas by less than 1,000-8,000 votes, and now, thousands of names have disappeared from the rolls.

This is why, beneath Chief Minister Mamata Banerjee's claim that the TMC will return with a bigger mandate than the 215 seats it won in 2021, and Union Home Minister Amit Shah's assertion that the BJP will cross 170 seats from its present tally of 77, both parties are quietly fighting a grimmer battle -- one booth, one deleted voter and one marginal constituency at a time.

More than 90.83 lakh names have been deleted across West Bengal till April 7, nearly 11.85 per cent of the electorate identified last October. Of those, 27.16 lakh deletions came from the "under adjudication" category alone.

The epicentre lies in nearly 70 seats across 11 districts. Twenty-five are in Kolkata and the adjoining belt of North 24 Parganas, Howrah and Hooghly. The rest are in Murshidabad, Malda, Bankura, Purulia, the two Bardhamans and the two Medinipurs.

North 24 Parganas alone has 13 such closely fought seats, Murshidabad 10, Bankura-Purulia nine, Howrah-Hooghly eight and the twin Medinipurs and Bardhamans another eight.

The 2021 election showed how narrow the divide had become. Of the 57 seats decided by 8,000 votes or less, the TMC won 29 and the BJP 28. In the 19 seats where the margin was below 3,000, the BJP won 12 and the TMC seven.

Kulti in Paschim Bardhaman was won by the BJP by just 679 votes. Dantan by 623, Ghatal by 966, Bankura by 1,468, and Nandigram, where Suvendu Adhikari defeated Mamata Banerjee, by 1,956.

Kulti has seen around 38,000 names deleted -- more than 50 times the victory margin. Nandigram -- the BJP's most symbolic victory and the constituency that turned Adhikari into the saffron camp's key leader -- has witnessed 14,462 deletions, more than seven times the margin by which Banerjee lost there.

In North 24 Parganas and Nadia, where the BJP has tried to build a Hindu refugee-Matua coalition around the citizenship issue, the mismatch between margins and deletions is even starker.

Bongaon South, which the BJP won by around 2,000 votes, has seen nearly 7,000 names deleted. Kalyani, another BJP-held seat won by roughly 2,000 votes, witnessed around 9,000 deletions.

In North 24 Parganas, more than 55 per cent of the names kept under scrutiny were eventually deleted. In Nadia, the figure was nearly 78 per cent.

Murshidabad, one of the TMC's strongest districts, saw the sharpest under-adjudication deletions -- 4.55 lakh names. Together with earlier deletions, the district has lost nearly 7.49 lakh voters. North 24 Parganas lost over 12.6 lakh names in the two phases combined, while Malda lost 4.59 lakh. South 24 Parganas saw over 10.91 lakh names disappear and Kolkata alone lost nearly 6.97 lakh.

Of the metropolis' 16 assembly seats, only Beleghata and Bhabanipur are estimated to have recorded SIR deletions lower than the previous victory margin. In every other constituency, deleted names exceed the winning margin.

One of the TMC's safest bastions, Bhabanipur, saw 51,005 names deleted, including 3,893 removed after being kept in the "under consideration" category. Yet, even there, the deletions remain below the scale of the TMC's victories. The party won the seat by around 29,000 votes in 2021, and Mamata Banerjee later retained it in the bypoll with a margin of nearly 58,000.

Dinhata perhaps remains the most dramatic anecdote of West Bengal's volatility. BJP's Nisith Pramanik beat TMC's Udayan Guha there by only 57 votes in 2021. Months later, after a bypoll, Guha returned with a margin of 1.64 lakh.

Before the adjudication process began, there were around 111 assembly segments where the number of voters under scrutiny exceeded the winning margin of the 2024 Lok Sabha polls in the segments. Even after the process, deleted voters outnumber the Lok Sabha victory margin in at least 120 assembly seats.

The scale of the churn becomes clearer in 44 assembly seats where the number of names struck off the rolls is greater than the margin by which the winner had prevailed in 2021.

The TMC holds 24 of these seats and the BJP 20, underlining that neither side is insulated from the impact of the revision. The BJP-held list includes emblematic constituencies such as Nandigram and Gaighata.

The cluster is spread across some of the state's most politically sensitive districts. Purba and Paschim Bardhaman and Nadia account for five such seats each. North 24 Parganas and Paschim Medinipur have four each, while Cooch Behar, Dakshin Dinajpur and Murshidabad have three each. Purba Medinipur and Howrah account for two each.

In effect, the faultline runs through both the BJP's expanding belt in northern and western Bengal and the TMC's entrenched strongholds elsewhere, making the impact of the deletions impossible for either camp to ignore.

Based on 2021 turnout patterns, a one per cent swing in vote share could flip at least 15 of these seats. A two per cent shift could alter more than 20.

"The BJP is using the commission to steal votes and delete names. But we have understood the game. The answer will be given through the ballot box," TMC leader Arup Chakraborty said.

The BJP claims the revision has exposed "illegal Bangladeshi" and dead voters while ending the scope for bogus voting.

"In 2024, the BJP lost several seats because the Left dented anti-TMC votes. If that vote consolidates and even a few thousand fake voters' names go out of rolls, these 65 seats can completely alter the result," BJP leader Debjit Sarkar said.