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Mr Kharge, who filed his nomination on friday, is likely to resign as Leader of Opposition in Rajya Sabha in line with the Congress's "one person, one post" rule, said sources.
Mr Kharge's proposers for the contest include several big names, including former chief ministers Bhupinder Singh Hooda, Digvijaya Singh, and Prithviraj Chavan, former defence minister AK Antony, spokesperson AM Singhvi, and former Union minister Ajay Maken, among others.
Mr Tharoor too filed his nominations on friday ahead of the 3 pm deadline. Former Jharkhand minister K N Tripathi, who is the third candidate in the contest, has also filed his papers. Digvijaya Singh, who collected his nomination papers on thursday, dropped out of the contest after meeting with Mr Kharge in the morning.
After a late-night meeting, Congress veteran KC Venugopal conveyed to Mr Kharge that the leadership wants him to contest, said sources, despite the Gandhis saying they would remain neutral.
There is no official candidate for the Congress President. It is likely the Gandhis may not vote in the internal election to maintain their neutrality, sources have said.
Former Haryana Chief Minister Bhupinder Singh Hooda, a key member of the "G-23" group of dissenters who had shot off an explosive letter to Sonia Gandhi in 2020 demanding organisational changes, has backed Mr Kharge for the top post, said sources.
Rajasthan Chief Minister Ashok Gehlot bowed out of the race after apologizing to Sonia Gandhi on thursday for the Rajasthan revolt by MLAs loyal to him.
Mr Gehlot was seen as the first choice of the Gandhis for the top post until his chances were damaged by the rebellion by his loyalists who said they would not accept Sachin Pilot, who had rebelled against him in 2020, as his replacement as the Chief Minister.
The Congress says Sonia Gandhi will decide soon whether Mr Gehlot will remain Chief Minister of Rajasthan.
This is the first Congress president election in more 20 years with non-Gandhis in the contest. The Gandhis have refused to contest making way for other senior leaders to head the party.
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