NAVI MUMBAI, Dec. 18 -- Navi Mumbai's political landscape saw a major shake-up on Tuesday night as five former municipal corporators from the Shiv Sena (UBT) and the Congress joined the Eknath Shinde-led Shiv Sena, dealing a sharp blow to the opposition exactly a month ahead of the long-delayed civic elections. The most significant switch came from MK Madhavi, a four-time corporator from Airoli, Sena (UBT) candidate in the 2024 assembly elections, and a key organiser of the party in Navi Mumbai. Madhavi joined the Shinde camp along with his wife Vinaya and son Karan, both former corporators, with Karan considered close to Sena (UBT) leader Aaditya Thackeray. Madhavi's daughter-in-law, Tejashree, likely to contest the upcoming civic election, also joined the Sena. From the Congress, former Belapur corporator and Navi Mumbai Congress district president, Poonam Patil, switched sides with her husband Mithun and brother-in-law Amit, the latter a former Congress corporator. Poonam is the daughter of NCP city chief Namdeo Bhagat. Interestingly, Poonam follows a number of former Congress leaders from Navi Mumbai, who were city chiefs, to defect in recent years, mostly to the BJP, further weakening the party's municipal footprint. The induction took place late at night in Thane, in the presence of deputy chief minister and Shiv Sena chief Eknath Shinde, at a gathering organised by party MP Naresh Mhaske. It underscored the Sena's aggressive push to consolidate its civic base ahead of the polls. Explaining the switch, Madhavi said the move was driven by personal considerations and the need to push local development. "For my workers in my ward, and for the development of the ward, I have joined the party. I want to work under the leadership and guidance of our Shiv Sena leader." Welcoming the new entrants, Shinde said the defections reflected confidence in his leadership and governance model. The defections are being seen as particularly damaging for the Sena (UBT) and the Congress in Navi Mumbai, where both parties have struggled to retain senior corporators and finalise strong ward-level panels....