Chennai:
Voting in the by-election for the Pudukottai assembly constituency began at 8 am on Tuesday.
The by-poll in Pudukottai, 350 km from Chennai, was necessitated following the death of CPI legislator SP Muthukumaran in a road accident in April.
It would be a straight fight between the ruling AIADMK and DMDK, with DMK and others boycotting the polls.
The DMK had charged that the opposition parties will not get justice from the Election Commission.
The CPI decided not to contest the poll considering the practical weakness in facing the by-poll.
The two major choices before the Pudukottai voters are the ruling AIADMK candidate Karthik Thondaiman and the opposition party DMDK's N. Jahir Hussain.
Pudukottai constituency has 224 polling booths and over 190,000 voters.
Currently in the 235-member Tamil Nadu assembly, AIADMK has 150 members (including the speaker) followed by DMDK's 29, DMK's 23, CPI-M's 10, CPI's eight, Congress's five and PMK's three, among others.