Former prime minister Manmohan Singh on Tuesday filed nomination papers for the bypoll to Rajya Sabha from Rajasthan.
Singh filed the nomination papers in the chamber of the returning officer in the Rajasthan assembly, sources said.
He was accompanied by Rajasthan chief minister Ashok Gehlot, deputy chief minister Sachin Pilot, All India Congress Committee general secretary in-charge of Rajasthan Avinash Pande, Rajasthan parliamentary affairs minister Shanti Dhariwal, chief whip Mahesh Joshi, health minister Raghu Sharma and others.
The seat got vacant after the death of Bharatiya Janata Party's Rajya Sabha MP Madan Lal Saini in June.
Rajasthan has 10 Rajya Sabha seats.
The Congress has the majority in the state assembly and Singh, 86, is likely to win the bypoll.
The Rajasthan assembly has 200 seats, two of which are vacant.
The Congress has 100 MLAs and its alliance partner Rashtriya Lok Dal has one seat.
The Bharatiya Janata Party has 72 while the Bahujan Samaj Party 6, the Bharatiya Tribal Party, the Communist Party of India-Marxist and the Rashtriya Loktantrik Party have two seats each.
Thirteen MLAs are independents and two seats are vacant. -- PTI