Setting in motion the end of his run as Bihar’s longest-serving Chief Minister, Nitish Kumar on Thursday filed nomination papers for the coming Rajya Sabha elections. This clears the decks for a new CM, likely from the BJP, to take charge, and has left many in the JD(U) in disbelief.

Kumar, BJP president Nitin Nabin, his party colleague Shivesh Ram, JD(U)’s Ram Nath Thakur, and Rashtriya Lok Morcha chief Upendra Kushwaha submitted their nomination papers at the office of the Bihar Vidhan Sabha In-charge Secretary Khyati Singh. They were accompanied by Union Home Minister Amit Shah.

Hours earlier, announcing the decision on X, Kumar thanked the people of Bihar for their “trust and support” for over two decades. “Since the beginning of my parliamentary life, I had a desire to become a member of both Houses of Parliament, in addition to being a member of both Houses of the Bihar legislature. In keeping with this aspiration, I seek to become a member of the Rajya Sabha in the elections being held this time. I want to assure you with complete honesty that my relationship with you will continue in the future as well, and my resolve to work together with you to build a developed Bihar will remain steadfast. The new government that will be formed will have my full cooperation and guidance,” the JD(U) leader wrote.

Shah also praised the JD(U) chief for leading Bihar “out of jungle raj” and towards “development and good governance”. “His vast experience in public service and deep understanding of policy-making will make the proceedings of the Rajya Sabha even more effective. Your esteemed presence will further strengthen the NDA’s resolve of ‘Sabka Saath, Sabka Vikas’,” Shah wrote.

The Union Home Minister later told reporters that Kumar had been a “yashashwi (successful) CM” whose “tenure would be known as a golden period in Bihar politics”.

Nitish’s impending move to the Upper House comes months after he set a record by taking oath as CM for the 10th time. His departure from Bihar politics will mark the end of the dominance of the socialist parties, which began with Lalu Prasad’s election as CM in 1990 and then continued under Nitish.

Though Nitish has not yet resigned as CM — the Rajya Sabha elections are on March 16 and he can continue in the post till he takes oath in the Upper House (the terms of the members whose seats fall vacant expire on April 9) — the NDA has started the process of power transfer. Sources in the CM House told The Indian Express that Nitish would resign “only after he receives a clear power transfer proposal from the BJP”. He, the insiders said, will ensure a “CM of his choice” from the BJP. The JD(U is most likely to have two Deputy CMs: Nitish’s son Nishant Kumar and senior minister Vijay Kumar Choudhary, who is Nitish’s trusted aide, it is learnt.

While Deputy CM Samrat Choudhary remains the frontrunner to succeed Nitish, other names such as Deputy CM Vijay Kumar Sinha, Union MoS Nityanand Rai, state industries minister Dilip Jaiswal, EBC leaders Sanjeev Chaurasia and Pramod Chandravanshi, and Dalit leader Janak Ram are also in contention, it is learnt.

Nitish’s decision to give up the CM chair took many of his party colleagues and supporters by surprise. Earlier in the day, dozens of JD(U) workers and supporters thronged 1, Aney Marg, the CM’s official residence. At one point, irate JD(U) workers tried to stop state minister Surendra Mehta and JD(U) leader Sanjay Gandhi from entering the CM House.

In the crowd, emotions ran high as people expressed their pride in having had Nitish as CM, but also conveyed a sense of anger about the decision, saying they had been let down. Many directed their anger at JD(U) national working president Sanjay Jha and Union Minister Rajeev Ranjan Singh, popularly known as Lalan Singh. “When the NDA won on the basis of the slogan, ‘2025 se 2030, phir se Nitish (Nitish from 2025 to 2030), why is he being forced to go to the Rajya Sabha? Jha and Singh completed Operation Lotus,” said JD(U) leader and Bhoomi Sangharsh Sena chief Rupesh Patel. Some supporters labelled Jha and Singh “Vibhishan (traitor)”.

Lalan Singh briefly appeared before the media to say the CM had made the decision. “It is his call,” he said.

Barun Kumar Singh, a party leader from Fatuha in Patna district, said, “I have known Nitish Kumar since 1985, when he won his first election from Harnaut (in Nalanda) … The best thing about Nitish Kumar is that he never had the tag of a caste leader. He belonged to all of us and brought about a turnaround of the state in terms of infrastructure and other development indices. We are proud to have witnessed the golden era of the state under Nitish. Sending him to the Rajya Sabha is just an excuse to retire him from Bihar politics.”

JD(U) minister Ashok Kumar Choudhary said he grew emotional thinking about Nitish moving out of Bihar politics. “Ye neta ka faisla hai (Going to the Rajya Sabha is our leader’s call).”

In the afternoon, when the CM emerged from the residence on his way to file the nomination along with Shah and Nabin, JD(U) workers gathered outside shouted in unison, “Nitish Kumar zindabad.”

An atmosphere of disbelief prevailed in some quarters of the JD(U) leadership, too. “We knew it was going to happen, but we never knew it would happen so soon. Nitish Kumar’s decision has put the JD(U) at a crossroads. He has put so much pressure on the shoulders of his son Nishant, who has to learn fast and evolve as a strong leader to save the JD(U),” said a source close to the CM House.