Nitish Kumar, 75, is likely to file his nomination for the Rajya Sabha as a Janata Dal (United) nominee on Thursday, sparking speculation over who will replace him as the Bihar chief minister.
Kumar's son, Nishant, is set to join the JD(U) on Thursday and may be inducted as a deputy chief minister.
The JD(U) has not named any candidates for the Rajya Sabha elections, but it can win two seats on its own and help an NDA candidate secure another.
Union minister Giriraj Singh refuted speculation about Kumar's Rajya Sabha nomination, saying such jokes are common on Holi.
Kumar has been the central figure in Bihar's politics for nearly two decades, and his possible shift to Delhi could reshape the ruling NDA in the state.
The BJP is widely expected to get the chief minister's post if Kumar steps down, and the party is believed to have begun internal discussions and political assessments in anticipation of a post-Kumar scenario.
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.
The BJP is expected to factor in both caste arithmetic and expectations of women voters while picking its chief ministerial candidate.
Political observers say the BJP leadership is likely to look for a formula that preserves the coalition's balance.
