Bihar Voter Roll Revision Impact: Analysis Shows Potential Influence on Over 100 Assembly Seats

Bihar's Special Intensive Revision (SIR) data as of September 30, 2025, reveals a significant statewide reduction of 4.88 percent in registered voters compared to January 1, 2025 figures. The January data serves as the benchmark since detailed constituency information is available on the Election Commission's portal in Form 2B.

M76 Analytics employed Artificial Intelligence tools and algorithms to extract data from approximately 90,000 scanned voter block documents across all 243 Assembly constituencies, enabling a precise constituency-level comparison of voter numbers.

The analysis shows an average reduction of 15,809 voters per Assembly seat, with notable regional variations. Seemanchal experienced the highest voter reduction, followed by Bhojpur region, while Magadh recorded the smallest decrease in voter numbers.

This revision's potential impact on regional political dynamics appears significant when examined against the 2020 Assembly election results. In Seemanchal, where RJD+ and NDA were previously evenly matched with AIMIM claiming 11 percent of votes, the electoral equation could shift. Notably, four of five sitting AIMIM MLAs have already joined RJD, complicating predictions about the SIR exercise's effects.

Bhojpur, with the second-highest voter reduction at 5.56 percent, was a region where RJD+ previously held a strong 7-percentage-point advantage over NDA. The SIR impact may be particularly pronounced here.

While NDA maintained clear advantages in Anga Pradesh, Mithilanchal, and Tirhut regions, Magadh remains an RJD+ stronghold with minimal voter reduction.

The voter reduction appears distributed across regions supporting both major alliances, suggesting the SIR exercise hasn't disproportionately affected either NDA or RJD+.

To evaluate potential election outcome influences, constituencies were categorized based on voter roll reductions relative to the 4.88 percent average. With the 2020 average victory margin at 9.7 percent, approximately 107 seats could see their results attributed to the SIR exercise in post-election analysis.

Most critical are 31 seats where the average victory margin of 11.74 percent coincides with voter reduction exceeding 7.27 percent. Even party strongholds in this category could experience significant impacts.

The SIR revision has substantially reduced voter numbers across Bihar, with the most significant decreases in Seemanchal and Bhojpur. While these changes affect all political parties' territories, their true electoral impact remains to be seen. Current data indicates over 100 seats could potentially be influenced by these voter roll revisions.