The Nationalist Congress Party's Chandrakant Danve won the bypoll to the Bhokerdhan assembly constituency in Maharashtra's Jalna district.
Danve defeated his nearest rival, Bharatiya Janata Party candidate Shivaji Thote, by a margin of 16,676 votes, securing 74,918 votes.
The bypoll was necessitated by BJP MLA Vitthal Sakpal's death.
Danve, son of former BJP MP Pundalikrao Danve, had recently defected to the NCP.
There were seven candidates in the fray.
Deputy Chief Minister Chhagan Bhujbal described the win as a victory of secular forces. "The Modi pattern will not work in Maharashtra," he said.
Danve was supported by the Congress, NCP's main partner in the ruling coalition in the state.
