The bye election was necessitated by the resignation of the sitting MLA, Dibyendu Adhikari, as he was elected as MP in the Indian Parliament from Tamluk Lok Sabha Constituency on 19 November 2016.
.# Swing calculated on Congress+Trinamool Congress vote percentages taken together in 2006. 2009 by election not taken into consideration because of lack of sufficient data.
.# Swing calculated on BJP+Trinamool Congress vote percentages taken together in 2006. 2009 by election not taken into consideration because of lack of sufficient data.
In the 2006 state assembly elections Suvendu Adhikari of Trinamool Congress won the Contai South assembly seat defeating his nearest rival Satyendra Nath Panda of CPI. Contests in most years were multi cornered but only winners and runners are being mentioned. Sisir Adhikari of Trinamool Congress defeated Sukhendu Maiti of CPI in 2001. Sailaja Kumar Das of Congress defeated Sukhendu Maity of CPI in 1996 and 1991. Sukhendu Maity of CPI defeated Sailaja Kumar Das of Congress in 1987. Sisir Adhikari of Congress defeated Deepak Mondal, Independent, in 1982. Satyabrata Maity of Janata Party defeated Sudhir Chandra Das, Independent, in 1977.[9]