In Palghar, the bypoll was necessitated following the death of sitting BJP MP Chintaman Wanaga. The BJP's bickering ally Shiv Sena has fielded the late MP's son, Srinivas Wanaga, in a bid to garner the sympathy vote.
The BJP has put up former Congress minister Rajendra Gavit and the Bahujan Vikas Aghadi is also in the fray with the nomination of its ex-MP Baliram Jadhav.
Kiran Raja Gahla of the CPI-M, which has a base in Talasari and Dahanu areas, and former MP Damu Shingada (Congress) are also contesting in a multi-cornered fight from the Palghar seat, reserved for Scheduled Tribes (ST).
The Sena had earlier accused the BJP of distributing cash to voters.
During a rally, Sena chief Uddhav Thackeray played an audio clip wherein Chief Minister Devendra Fadnavis purportedly exhorted the party cadre to win the elections "by all means possible." Fadnavis had said the audio recording was doctored.
An editorial in the Sena mouthpiece 'Saamana' on Monday said its nominee will win the Palghar seat, despite the BJP
In Bhandara-Gondia, the BJP and the NCP have locked horns in the bypoll, being held after the resignation of BJP MP Nana Patole..
Patole, a leader of the powerful OBC Kunbi community, had switched side from the Congress to the BJP and was elected as an MP from the constituency, located in the Vidarbha region, in 2014 by defeating former Union minister and NCP heavyweight Praful Patel. The NCP, which has allied with the Congress, has fielded former BJP MLA Madhukar Kukde, against BJP's Hemant .
Patole, who belongs to the Powar community and is also a former legislator.