Dravida Munnetra Kazhagam (DMK) candidate Ezhilan N had defeated Bharatiya Janata Party (BJP) leader Kushboo Sundar from the Thousand Lights constituency.
The actor-turned-politician, Kushboo Sundar, had quit the Congress in October last year and joined the BJP. This was her third political stop in a career that had begun with the DMK only 10 years ago.
Meanwhile, DMK president MK Stalin, who is set to become the Chief Minister of Tamil Nadu for the first time, thanked the people for voting his party to power and assured them that he would truthfully work for them.
Stalin expressed his 'heartfelt thanks' to all the people of the state for mandating his party to govern Tamil Nadu for the sixth time.
According to the Election Commission data at 11 pm, DMK was leading in 93 segments of the total 234 in the state and won 40 seats, which is inclusive of its allies who fought on the party's rising sun symbol.
The All India Anna Dravida Munnetra Kazhagam (AIADMK) was leading in 51 and won 18 seats.
In the past, the DMK had been the ruling party five times, during 2006-11, 1996-2001, 1989-91, 1971-76 and 1967- 71.