Jahanabad is one of the 40 Lok Sabha constituencies in Bihar state. The constituency covers portions of the Arwal and Jehanabad districts which are hit by Naxalite insurgency. The development in the area is often hampered due to attacks by the Naxals.
Of the 40 seats in Bihar, 34 are unreserved seats and 6 are reserved for Scheduled Caste candidates. The Jehanabad parliamentary constituency comprises of three Vidhan Sabha segments, namely Jehanabad , Ghosi, Makhdumpur and Arwal. Out of these six Vidhan Sabha segments, Makhdumpur is reserved for Scheduled Caste candidates.
In the 2014 election, Rashtriya Lok Samta Party's Arun Kumar won the seat defeating Rashtriya Janata Dal's Surendra Prasad Yadav by a margin of 42340 votes.
While the seat saw Congress and Communist Party of India had a stronghold in the seat in the initial years, the seat has seen leaders from Janata Dal United, Rashtriya Janata Dal and Rashtriya Lok Samata Party win the polls. In the elections in 1957 and 1962, Congress's Satyabhama Devi won from the seat. In 1977, Hari Lal Prasad Sinha bagged the seat on a Janata Party ticket. In 1980, Mahendra Prasad won the seat back for the Congress. For the next four elections in 1984, 1989, 1991 and 1996, Ramashray Prasad Singh won the seat for Communist Party of India. In 1998, Dr Surendra Prasad Yadav won on an RJD ticket, in 1999 JDU's Arun Kumar emerged as a winner on a JDU ticket. In 2004, Rashtriya Janata Dal's Ganesh Prasad Singh won, in 2009, JDU's Jagdish Sharma won while in 2014, RLSP's Arun Kumar bagged the seat.
In 2014 election, Bihar witnessed an overall turnout of 56.28 per cent of which 57.66 per cent were female voters and 55.08 per cent were male voters. The Jehanabad seat saw an overall voter turnout of 57.02 per cent which included 54.76 per cent female and 59.04 per cent male voters.