PATNA, March 31 -- The longest-serving Bihar chief minister Nitish Kumar on Monday tendered his resignation from the state Legislative Council, triggering speculations about his successor and a wave of emotions from close confidantes and supporters who see his exit as the end of an era and the creation of a vacuum not easily filled. BJP national president Nitin Nabin also submitted his resignation as member of the Bihar Legislative Assembly. Both leaders sent their resignation letters through emissaries. While Sanjay Gandhi, a JD(U) MLC, accompanied by parliamentary affairs Minister Vijay Kumar Choudhary, carried Nitish Kumar's letter to the Legislative Council Chairman, BJP state president Sanjay Saraogi handed Nabin's letter to the Legislative Assembly Speaker. Bihar Legislative Council chairman Avadhesh Narayan Singh, who also paid a courtesy visit to the CM in the morning, said he had accepted Nitish Kumar's resignation. "I met the chief minister this morning as a courtesy visit. He has submitted his resignation. The seat will be declared vacant. Bihar is saddened by his departure... Today, Bihar is counted among the developed states. The resignation has been accepted. He has been an invaluable leader of the House and devoted himself to Bihar's cause," he said. Both the leaders were elected to Rajya Sabha on March 16 and the deadline of their resignation from the State Legislature was March 30. According to the Prohibition of Simultaneous Membership Rules, 1950 (under Articles 101/190 of the Constitution), a member elected to both Parliament and a State Legislature must resign from one within 14 days. On the other hand, Choudhary said that Nitish Kumar handed his resignation to Sanjay Gandhi for submission to the Speaker. "We have also reached the Assembly and are waiting for the Speaker to hand over the resignation letter," he added. Nitish's resignation, which he announced shockingly last month is a watershed in Bihar's much-storied political history. It was all the more dramatic as he is quitting only four months after securing another and a mammoth mandate in state polls. His succession is now the talk of the town. Most political pundits are hedging their bets on his deputy, Samrat Chaudhary, who is a BJP MLA and also from an OBC caste like Nitish. His Koeri caste is proverbially believed to strike a combination with Nitish's Kurmis which is known in local parlance as the Luv-Kush alliance. Pundits also admit that by making a Koeri the CM, the party may secure the support of the dominant OBC group for a long time, besides ending the perception that it was a "pro-upper caste" political force, which puts it at a disadvantage in a state like Bihar, where politics has for decades been influenced by the Mandal agitation of the 1990s. But then, in BJP, nothing can be said with certainty until it happens, they added. A constitutional provision allows a person to "remain the chief minister for up to six months after ceasing to be a member of the state legislature," but it is very unlikely that Nitish would stick to the post beyond the second week of April when he has to take oath as a Rajya Sabha MP. His health, a subject of conjecture for long, is also a probable factor in his decision to demit the office of the chief minister. Many in Patna political circles say that his foremost concern seems to be ensuring that his novice son secures a political place and his party gets a well-deserved share in the next Bihar cabinet. Nabin resigned as MLA from the Bankipur seat two weeks after he was elected to the Rajya Sabha. "The BJP president had pre-scheduled engagements in Delhi and Assam, besides some other work, on Sunday. Before leaving Patna, he had handed over his resignation to me, which I shall hand over to the Speaker today (Monday)," said Saraogi, who carried his resignation. Nabin himself wrote an emotional message to the people of Patna's Bankipur constituency, which he represented five times consecutively since 2006, Monday morning. "The party has given me a new responsibility, but my connection with my people will continue," he added. "I have accepted the resignation of Nitin Nabin. I have issued instructions to initiate the necessary further proceedings. An official letter has been issued, and a formal notification will also be released shortly. I have also received confirmation that the Chief Minister of Bihar has tendered his resignation within the Council. This is, truly, a deeply emotional moment; we have worked together for a very long time. Although this parting naturally evokes a sense of unease and concern, I remain fully confident that his focus will always remain squarely centred on the welfare of Bihar. Both of these leaders have consistently played a pivotal role in the politics of both the nation and the State of Bihar. Our bond is a long-standing one, it existed in the past, endures in the present, and will undoubtedly persist into the future," said Bihar Legislative Assembly Speaker Prem Kumar....