SIR redraws Bengal’s poll map; sharp churn in border belts, Matua axis, minority districts

Kolkata (PTI): The publication of West Bengal’s post-SIR rolls has not just pruned 63.66 lakh names from the electorate, it has redrawn the state’s demographic and political geometry ahead of the 2026 assembly polls, recasting voter profiles across districts, border belts and marquee constituencies just weeks before the campaign drums begin to beat.

With the electorate reduced from 7.66 crore to just over 7.04 crore - an 8.3 per cent contraction- and 60.06 lakh names placed under adjudication, the state enters a fluid pre-poll phase marked by significant voter churn.

The deletions are geographically concentrated and politically consequential.

"The SIR exercise introduces three structural variables into the 2026 contest: demographic filtering in border belts, stress on social coalitions in Matua and minority districts, and recalibration in urban and Junglemahal regions that have seen BJP’s expansion since 2019," political analyst Biswanath Chakraborty said.

The SIR has reshaped voter profiles across border districts, refugee-dominated pockets, minority-heavy belts, tribal zones and key urban constituencies. In a state where dozens of seats were decided by margins of 2,000–5,000 votes in 2021, even marginal shifts in rolls carry weight.

The sharpest churn is visible in districts bordering Bangladesh, where citizenship and migration politics have framed the contest between the TMC and the BJP.

In Nadia, 2.73 lakh names were deleted, reducing the electorate from 44.18 lakh to 41.45 lakh. North 24 Parganas saw its voter base shrink by nearly 10 lakh, from roughly 83 lakh to 73.88 lakh, with around six lakh names under adjudication.

In Muslim-majority Malda, the electorate fell from 32 lakh to 29.88 lakh, with nearly nine lakh names under adjudication. Murshidabad recorded 2.93 lakh deletions from a base of 57.64 lakh voters, while 11 lakh names remain under scrutiny. South 24 Parganas, the state’s largest district electorally, saw draft deletions of over 8 lakh, with around five lakh names pending adjudication.

Together, these districts influence more than 125 seats in the 294-member assembly. Minority-heavy belts such as Murshidabad, Malda and two 24 Parganas have traditionally delivered substantial leads to the TMC, often offsetting BJP’s gains in north Bengal and Junglemahal.

"If even a slice of the 60.06 lakh names under adjudication is clustered in these border and minority belts, the final corrections could redraw constituency margins in a state where several seats in 2021 and 2024 turned on a few thousand votes, small shifts in inclusion or exclusion can tilt the balance of power," another political analyst Suman Bhattacharya said.

The churn has been sharpest in the Matua belt across North 24 Parganas, Nadia and north Bengal, where leaders claim nearly 90 per cent of the community has been hit -- an assertion that, if validated, could reverberate across 40–50 seats where the Dalit Hindu refugee bloc anchors the BJP’s core vote bank.

For the BJP, the adjudication phase is both reinforcement and risk, strengthening its CAA plank while inviting backlash if refugee voters feel targeted. For the TMC, deletions in border and minority-heavy districts trigger urgent booth-level recalibration to protect its turnout-driven arithmetic.

In effect, the adjudication phase has introduced a layer of electoral uncertainty into districts that traditionally anchor the TMC’s statewide arithmetic while serving as the BJP’s principal expansion frontier. The battle for 2026, therefore, may hinge on how this demographic churn settles across these politically sensitive belts.

The TMC’s vote-margin over the BJP narrowed from around 61 lakh in the 2021 assembly elections to roughly 42 lakh in the 2024 Lok Sabha polls. The 2026 election is thus not a repeat of 2021’s landslide but a contest framed by tightening bipolarity.

In Kolkata’s urban core, traditionally a TMC stronghold, deletions have also drawn attention. North Kolkata’s seven Assembly segments together saw around 4.07 lakh deletions.

Across four South Kolkata constituencies -- Bhabanipur, Kolkata Port, Rashbehari and Ballygunge, the electorate dipped from 6,91,306 in the draft to 6,88,099 in the final phase, with 78,657 names under adjudication.

In Bhabanipur, represented by Chief Minister Mamata Banerjee, 47,094 names were struck off across the draft and final stages, with over 14,000 electors under adjudication. The deletions are roughly 11,000 fewer than Banerjee’s 2021 bypoll victory margin of over 58,000 votes.

Yet in Nandigram, the high-voltage constituency represented by Leader of Opposition Suvendu Adhikari, the final rolls show a net addition of 770 voters compared to the draft list, taking the electorate to 2,68,378. In 2021, Nandigram was decided by just 1,956 votes.

Paschim Medinipur saw total deletions rise to over 2.21 lakh, with over one lakh under adjudication.

Jalpaiguri in north Bengal recorded deletions of roughly 1.5 lakh since SIR began, bringing its electorate down to around 17.48 lakh. Alipurduar in north Bengal recorded 1,02,835 deletions, with 11,96,651 names featuring in the final rolls. These belts, particularly Junglemahal and north Bengal, were BJP growth zones in 2019 and 2021.

"The more consequential number is not the deletions already counted, but the names still under adjudication — a pending ledger that could continue to reshape booth arithmetic even as campaign gains momentum," a TMC leader said.