| Name of the Candidate | Party Name | Result |
| SANTOSH KUMAR NIRALA | Janata Dal (United) | 84184 |
| BISHAWNATH RAM | Bharatiya Janata Party | 51396 |
| LALJI RAM | Bahujan Samaj Party | 17031 |
| AJAD PASWAN | Suheldev Bhartiya Samaj Party | 5540 |
| RAJ BALI RAM | Independent | 3495 |
| SURENDRA PASWAN | Independent | 2940 |
| RAMASHANKER RAM | Communist Party of India (Marxist-Leninist) (Liberation) | 2143 |
| ANAND BARDHAN | Jan Adhikar Party (Loktantrik) | 1376 |
| MANOJ KUMAR RAM | Independent | 1302 |
| JAGDISH PASWAN ALIAS JAGDISH RAM | Independent | 717 |
| CHHEDI LAL RAM | Samajwadi Party | 614 |
| VIRENDRA KUMAR | Shivsena | 518 |
| NIWAS RAM DUSADH | Bahujan Mukti Party | 500 |
| MANOJ KUMAR | Jharkhand Mukti Morcha | 424 |
| TARKESHWAR PASWAN | Garib Janta Dal (Secular) | 415 |
| None of the Above | None of the Above | 2941 |
| AC No | Category | Poll Phases | Last Date of Nominations | Date of Polls | Result |
| 202 | SC | Phase III | Oct 1st 2015 | Oct 28th 2015 | Nov 8th 2015 |
Rajpur legislative assembly segments is located in the Buxar district. It is a part of the Buxar Lok Sabha constituency. There ia total of 2,85,849 voters amongst them 1,50,306 are males and 1,35,543 are females. The constituency is reserved for the candidates belonging to Scheduled Castes (SCs). Rajpur assembly segment comprises Ataon, Kanjharua, Mathila, Mugaon, Kasian and Koransarai gram panchayats of Dumraon community development block; Rajpur community development block; and Itarhi community development block.
Reserved or the candidates belonging to the scheduled castes, Rajpur assembly constituency is currently held by Santosh Kumar Nirala who retained the seat for the Janata Dal (United) it in the last general assembly elections in Bihar in 2010 by defeating his nearest Lok Janashakti Party (LJP) candidate and former MLA Chhedi Lal Ram by a margin of 15239 votes.
Santosh Kumar Nirala was given ticket after the sitting JD (U) MLA Shyam Payari Devi's death.
In that election, Santosh Kumar Nirala polled 54802 votes as against 39563 votes received by Chhedi Lal Ram who was followed by Pankaj Kumar of the Mayawati led Bahujan Samaj Party (BSP) who obtained 18389 votes. Manju Kumari, who entered the fray on the ticket of the Congress, was relegated to the fourth place with just 5614 votes and lost her deposit. A total of 14 candidates contested the assembly election to Rajpur in 2010.
In both the elections to the Rajpur assembly seat held in 2005, Shyam Payari Devi had defeated Santosh Kumar Nirala who had entered the fray as BSP candidate on both the occasions. In 2000, the seat went in favour of Chhedi Lal Ram, then a BSP candidate, who had trounced Kamakhya Narayan of the RJD by a margin of 1615 votes.
In the previous assembly elections in 1995 the seat was won by Arjoon Ram of the CPI who had defeated Chhedi Lal Ram.
One of the four assembly constituencies located in the Buxar district, Rajpur assembly seat was claimed by the BHP in 1985 and 1990 when its candidate Ram Narain Harijan emerged victorious from the seat. Whille he defeated Arjoon Ram in 1990, in 1985 he trounced Nand Kishore Prasad of the Lok DAL. Nand Kishore Prasad was elected on the ticket of Janata Party in 1977 from the Rajpur assembly constituency.
Dumraon, Buxar and Brahampur are the other three assembly constituencies located in the Buxar district.
Rajpur is one of the six assembly constituencies that combine to create the Buxar parliamentary constituency currently represented by Ashwani Kumar Choubey of the BJP who retained the seat for the BJP by defeating his nearest rival and sitting RJD MP Jagada Nand Singh by a margin of 1,32,338 votes in the last parliamentary elections in 2014.
Dumraon, Brahampur, Buxar, Dinara and Rajpur are the other six assembly constituencies falling under the Buxar Lok Sabha seat.
Sitting MLA Santosh Nirala of JD(U) is pitted against Vishwanath Ram of BJP in this reserved constituency in Buxar district. Rajpur assembly seat is occupied by Santosh Kumar Nirala of JD (U), who won the seat having bagged 54,802 votes in the assembly elections held in November 2010. LJP's Chhedi Lal Ram was the runner-up with 39,593 votes. The constituency is reserved for the candidates belonging to Scheduled Castes (SCs).