India, Jan. 14 -- It is back to the 1960s in Mumbai, going by the poll rhetoric of the Thackeray cousins. Politically cornered and weakened by splits, the Shiv Sena (UBT) of Uddhav Thackeray and the Maharashtra Navnirman Sena of Raj Thackeray have fallen back on Marathi identity concerns to stay in the race to retain the Brihanmumbai Municipal Corporation (BMC). The pre-split Shiv Sena was an ethusiastic espouser of the Hindutva agenda - and this worked electorally in Mumbai, which has seen a rise in migration from northern India. But with the Thackerays falling out with the BJP, they have sought to set the clock back, claiming that "this (the election) was the final battle for Mumbai and Marathi manoos (people)". Their shrill campaign has flagged issues such as capital moving out of Maharashtra to Gujarat, militant vegetarianism, and the Mahayuti government's aborted move to introduce the three-language formula in schools, in a bid to rally the Marathi manoos. Marathi identity birthed the Sena, and propelled it in its initial years, but it remains to be seen if identity politics will work in the new Mumbai, a cosmopolitan city of 20 million people, of which native Marathi speakers account for just about 30%. There has been a resurgence of singular identities in politics - mostly faith-centric - but, in the context of Mumbai, this signals poor political imagination. Sadly, the BJP, which started its campaign with a focus on recent investments in public infrastructure, has taken a cue from the Thackerays and changed its tune. In all this, the opportunity to audit the state of BMC, its thin finances, lack of vision for the ever-growing city, and the skillset of aspiring corporators and employees has been lost. Mumbai is not just a rich municipal corporation but a major engine of the Indian economy, and the financial and commercial capital of the world's forurth largest economy. Its governance has consequences beyond the city and even the state. Unfortunately, political parties have preferred to slug it out over narrow identities....