New Delhi, March 6 -- Nitish Kumar, 75, on Thursday announced his candidature for the Rajya Sabha as a Janata Dal (United) nominee, triggering speculation over who will replace him as the Bihar chief minister months after the National Democratic Alliance (NDA) swept back to power in the state. In a post X, Kumar expressed gratitude to the people of Bihar for trusting him for over 20 years, saying their support enabled him to serve the state with dedication. "The strength of your faith and support has helped Bihar present a new dimension of development and dignity," Kumar said. He added that he had expressed his gratitude to the people on several occasions earlier. Kumar said that since the beginning of his parliamentary career, he nurtured a desire to become a member of both Houses of Parliament in addition to serving in both Houses of the state legislature. "In that sequence, I wish to become a member of the Rajya Sabha in the election being held this time," he said. Kumar reassured people that his relationship with them would remain unchanged despite the move. He said he would continue working with the people to fulfil the goal of building a developed Bihar. Kumar added he would extend full cooperation and guidance to the new government that takes charge in the state. Kumar has been the central figure in Bihar's politics for nearly two decades. His shift to Delhi could reshape the ruling NDA in the state. Kumar is expected to vacate the chief minister's post only after the nomination process, election, and oath as a member of Parliament are completed. The Bharatiya Janata Party (BJP) is widely expected to get the chief minister's post. Union home minister Amit Shah on Thursday described chief minister Nitish Kumar's over two-decade rule as a golden period for Bihar, as the latter filed his nomination for the Rajya Sabha. "It is unprecedented for any political leader to have a spotless career even after four decades in public life, when he served in various capacities as Union minister and Bihar chief minister since 2005. His tenure has been highly successful, and he rid the state of jungle raj. He ensured road connectivity and electricity across the state. He lent speed to all aspects of the state's progress," said Shah The BJP has long been the dominant partner in the alliance in terms of organisational strength and electoral performance, even though the top post in Bihar has remained with Kumar. BJP leaders are believed to have begun internal discussions and political assessments in anticipation of a post-Kumar scenario. The BJP leadership is expected to balance multiple factors while choosing Kumar's successor. The decision will not only be about seniority but also about caste representation, coalition stability, and the broader political message the party wants to send. Caste dynamics continue to play a decisive role in Bihar's politics, and any leadership change will take that into account. Extremely Backward Classes (EBC) are among the most influential social groups in the state. Over the years, the EBCs have largely been seen as supporters of the NDA. Political strategists believe that the next chief minister will come from a social background that reassures this important voter base and helps maintain the coalition's social cohesion. Women voters are another important factor. In the 2025 election, women's participation increased significantly, and welfare programmes targeting them were credited with boosting support for the NDA. Networks of women associated with self-help groups, popularly referred to as "Jeevika didis", emerged as a strong pillar of the ruling alliance's electoral support. The BJP is expected to factor in both caste arithmetic and expectations of women voters while picking its chief ministerial candidate. It may lead the government, but it will have to ensure that its allies back the arrangement. The JD(U) will continue to remain an important partner in the NDA and retain influence among several communities. Nitish Kumar on Thursday announced that he will be resigning as chief minister and moving to the Rajya Sabha after two decades of leading the state government. "From the very beginning of my parliamentary journey, there has been a desire in my heart to become a member of both Houses of the Bihar Legislature as well as both Houses of Parliament. In keeping with this aspiration, I seek to become a member of the Rajya Sabha in the elections being held this time", Kumar posted on his official X account. Kumar has been a member of the Lok Sabha, Bihar Legislative Assembly and Bihar Legislative Council. The development comes the same day when Union home minister Amit Shah will be visiting Patna and likely to induct of his son Nishant Kumar into the Janata Dal United (JD-U) fold. Smart leader In the 2020 Bihar assembly pools, JD(U)'s tally in the assembly shrunk to 43, lowest since 2005 due to the emergence of the Lok Janshakti Party (LJP) which continued to be part of the larger National Democratic Alliance (NDA) grouping at the Centre. In 2025, JD-U won 85 seats at a strike rate of 85% despite Kumar's muted campaign amid concerns over his health. The announcement of women-centric welfare schemes, Rs 10,000 cash handout to 14.1 million women, resonated with people while he remained a vital figure for NDA in the run up to the 2025 assembly polls. On ground, there was a palpable undercurrent of support for Bihar's 'Sushashan Babu'. Experts attribute Kumar's success to his state government's consistent plans. "If women emerged as a big constituency favouring him despite the caste divide, it was a result of his government's consistent plans and policies since 2005," says analyst Prof. NK Choudhary, who retired as head of economics department from Patna University. "If the cycle scheme gave wings to girls and created a craving for education despite questions over the quality of schools, the reservation of 50% in panchayati raj and urban local bodies empowered women by involving them in grassroots governance," he added. Kumar also launched the Jeevika self-help group for rural women to become economically self-reliant. Soon after taking over as chief minister in 2005, Kumar also set out to upgrade the state's poor infrastructure. In 2005, his first stint as Bihar's chief minister, Nitish Kumar continued to work towards improving the state's infrastructure. DM Diwakar, the former director of AN Sinha Institute of Social Studies, Patna said Nitish's focus on improving roads, power, law and order saw him voted back to power in 2010. Born in the small town of Bakhtiyarpur in 1951 in a middle-class family, Kumar was influenced by socialist leader Ram Manohar Lohia and took the plunge into politics even though he was an engineering graduate. He entered Bihar assembly in 1985 and backed Lalu Prasad as leader of opposition in 1989. A year later, he supported Lalu Prasad's bid for CM . In 1994, the two fell out and in 1996, he aligned with the BJP. He was inducted as railway minister in the Atal Bihari Vajpayee government in 1998. On March 3, 2000, he became chief minister of Bihar for the first time when he was already a four-time MP, but his term lasted only seven days, as he failed to prove his majority. He did not have the seven votes required to pass the trust vote on the floor of the assembly....