India, Jan. 15 -- In the bylanes of Mankhurd last week, actor-turned-politician Manoj Tiwari, standing on a campaign chariot, breaks into an impromptu Bhojpuri song, weaving the local Bharatiya Janata Party (BJP) candidate Navnath Ban's name into the lyrics. Amid loud cheers, the BJP MP from Delhi says, "You will realise that electing Navnath is like electing chief minister Devendra Fadnavis."

It's a familiar election scene, but this time, the BJP executed it at scale, across languages and neighbourhoods, as it sought to navigate Mumbai's complex electoral battleground ahead of the Brihanmumbai Municipal Corporation (BMC) polls on Thursday.

Over 50 prominent leaders from outside Maharashtra-ranging from MPs and MLAs to mayors, cultural ...