Behind the ruling NDA’s landslide return to power in the Bihar Assembly elections lie record high victory margins, particularly for the Chief Minister Nitish Kumar-led Janata Dal (United).
This year, the winning candidates in Bihar set new state records for average margin as well as median margin (which refers to the midpoint of the margins recorded across all seats, eliminating the impact of outliers that tend to skew the average figures). While the average victor’s margin is 20,940 votes, the median margin is 18,510, breaking the previous records set in the 2015 Assembly polls.
[Historical margins in Bihar]The JD(U), for instance, nearly doubled its seat tally – from 43 in 2020 to 85 now – and saw its average winning margin rise from under 12,300 votes to over 23,620 votes. The party also improved its media margin from 10,440 votes to 22,550 votes this time. This turnaround was most likely impacted by the Chirag Paswan-led Lok Janshakti Party (Ram Vilas)’s return to the NDA fold after contesting the 2020 elections independently and cutting into the JD(U)’s votes in 32 seats.
Among the two major alliances, while the JD(U) recorded the highest margins, the BJP followed it with an average margin of 23,000 votes and a median margin of 21,860 votes, en route to emerging as the single-largest party with 89 seats. The BJP, too, improved on its performance in 2020, when its average margin was 19,360 votes and median margin was 16,300.
Party-wise margins in 2025
The LJP(RV)’s performance was particularly notable for its marked improvement from 2020, when it won just 1 seat with a narrow margin of 333 votes. This time, the party won 19 of the 28 seats it contested, with an average margin of 20,930 votes and a median margin of 20,320 votes.
However, in the Opposition Mahagathbandhan, the Tejashwi Prasad-led Rashtriya Janata Dal (RJD) suffered a major drop-off from 2020, when it had emerged as the single-largest party with 75 seats. This time, it has managed just 25 seats, winning them by an average margin of 10,190 votes and a median margin of 8,110 votes. In comparison, the party had recorded an average margin of 16,360 votes and a median margin of 13,690 votes in the 2020 polls.
Meanwhile, the Congress’s abysmal performance that saw it drop to 6 seats from 19 in 2020 was also exemplified by its reduced winning margins. While its average margin dropped from 13,550 votes in 2020 to 7,200 votes this time, its median margin rose slightly from 6,330 votes to 7,210.
However, among the parties that won any seats this time, it was the AIMIM that had the highest average margin at 29,350 votes and highest median margin at 28,730 votes in the 5 seats that it won this time. In 2020, too, the AIMIM had won 5 seats but its average margin was slightly higher at 31,530, as was its median margin of 36,140.
On an individual seat level, the highest margin was recorded by the JD(U)’s Kaladhar Prasad Mandal in Rupauli at 73,572 votes. The JD(U) has won the Rupauli seat in consecutive elections since 2010. In 15 seats – all won by the NDA – the margin exceeded 50,000 votes. In fact, the Mahagathbandhan’s highest margin was secured by RJD’s Shankar Prasad in Paroo at 28,827 votes, good enough only to be the 63rd highest margin in the state.
The low-margin seats
With Bihar recording its highest ever voter turnout, there were 31 seats where the winner and runner-up were separated by less than 5,000 votes, including 11 seats where the margin was below 1,000 votes.
In these 31 low-margin seats, the Mahagathbandhan lost 16 seats, the NDA in 14 seats, and the AIMIM in 1 seat. The RJD lost the most such seats at 13, followed by the BJP at 6, the JD(U) at 4, the LJP(RV) and CPI(M-L)L at 3 each, the Hindustani Awam Morcha (Secular) and AIMIM at 1 each.
The winners in these 31 seats include the JD(U) in 9 seats, RJD in 8 seats, BJP in 4 seats, LJP(RV) and Congress in 3 seats each, and the Rashtriya Lok Morcha, CPI(M-L)L, BSP and Indian Inclusive Party (IIP) in 1 seat each. The I P Gupta-led IIP is part of the Mahagathbandhan.
[Low-margin seats]In the Sandesh seat, which saw the closest contest of this election, the JD(U)’s Radha Charan Sah defeated the RJD’s Dipu Singh by 27 votes. In this seat, Jan Suraaj candidate Rajiv Ranjan Raj spoiled the RJD’s prospects by securing 6,040 votes and finishing in third place. Here, NOTA also polled a sizeable 4,160 votes. The RJD had won this seat in 2020 by a 50,607-vote margin.
In another closely contested RJD bastion of Ramgarh in the Kaimur district, the BSP secured its only seat with candidate Satish Yadav defeating the BJP’s Ashok Kumar Singh by 30 votes. In this seat, the RJD’s Ajit Kumar placed third with 41,480 votes, and the Jan Suraaj’s Anand Kumar Singh placed fourth with 4,426 votes, while NOTA received 1,154 votes.
In the SC-reserved Agiaon seat, the BJP’s Mahesh Paswan won by a margin of just 95 votes ahead of the CPI(M-L)L’s Shiv Prakash Ranjan. Here, even NOTA exceeded the margin with 3,631 votes.
The JD(U)’s Chetan Anand won the Nabinagar seat by 112 votes, defeating the RJD’s Amod Kumar Singh.
In the Dhaka seat, the RJD’s Faizal Rehman emerged as the winner with a margin of 178 votes over the BJP’s Pawan Kumar Jaiswal.
The Congress that won only six seats in the state saw its Forbesganj candidate Manoj Biswas win by 221 votes, defeating the BJP’s Vidhya Sagar Keshari. In Chanpatia, the Congress’s Abhishek Ranjan won by 602 votes ahead of the BJP’s sitting MLA Umakant Singh.
In a very close triangular contest in Balrampur, AIMIM spokesperson Mohd Adil Hasan lost by 389 votes as LJP(RV) candidate Sangita Devi won. Here, the sitting CPI(M-L)L MLA Mahboob Alam finished in third place.
The RJD’s Rahul Kumar won Jehanabad seat by 793 votes as he defeated the JD(U)’s Chandeshwar Prasad.
In SC-reserved Bodh Gaya, sitting RJD MLA Kumar Sarvjeet retained the seat by defeating LJP(RV) candidate Shyamdev Paswan by 881 votes.
LJP(RV) candidate Arun Kumar won the Bakhtiarpur seat by defeating the RJD’s sitting MLA Aniruddh Kumar by 981 votes.