How did Bihar go from a 2020 cliffhanger to a 2025 landslide?

NEW DELHI: The 2020 assembly elections were a photo finish in Bihar and both major alliances ended up with almost the same vote share with a difference of just 0.03% in the votes polled between them. This time, the National Democratic Alliance (NDA) has around a0 percentage points lead in terms of vote share visa-vis the Mahagathbandhan (MGB) or Grand Alliance.

- Abhishek Jha and Roshan Kishore

As is often the case in the first-pastthe-post system, the seat share difference between the two alliances has increased more: a massive 68.7 percentage point lead for the NDA compared to just six percentage points in 2020. What really happened? Here is a breakdown of the electoral math, as it changed between the 2020 and 2025 elections in Bihar.

MGB retained its popular support, but NDA increased it significantly

While MGB's vote share is almost identical between 2020 and 2025 (37.23% and 37.9%), NDA’s has increased from 37.26% to 46.6%. Where did NDA. get its additional support from in these elections?

‘Around five percentage points of extra vote share has come from the two main constituents, namely, the Bharatiya Janata Party (BJP) and Janata Dal (United) or JD(U). That this has happened despite the two parties contesting a lower number of seats this time (202) than in 2020 (225) underlines the scale of their achievement. Among the two, it is the JD(U) which has increased its vote share more, as it was far behind the BJP last time (more on this later).