The state has a knack for going against the national trend when it comes to picking a winner
Post-Emergency - the 1977 general elections in Tamil Nadu were held for 39 seats. The result was a sweep (34 seats) for the Congress and its allies (AIADMK and CPI). This was completely opposite to the national trend that saw Indira Gandhi being punished for the Emergency.
1980 general elections - The result was a landslide victory for the Congress (Indira) and its ally DMK, winning 37 out of 39 seats. This was a big upset to the ruling AIADMK, which won only Gobichettipalayam and Sivakasi. Forming an alliance with the DMK proved invaluable to Indira on a national level.
A landslide victory for the Congress and its ally AIADMK, winning 37 out of 39 seats. DMK won the other two seats. This marked the start of the dominance of INC-AIADMK for the next decade, winning 38 seats in 1989 and all 39 in 1991.
Rajiv Gandhi was voted out because of the Bofors scam but the story was different in Tamil Nadu. The result was a landslide victory for Congress and its ally AIADMK, winning 38 out of 39 seats. INC-AIADMK dominated the state till 1996.
1991 general elections - A repeat landslide victory for INC and AIADMK. The Opposition party didn’t win a single seat.
A landslide victory for the newly-formed alliance between the DMK, Tamil Maanila Congress (TMC), and the Left parties who ended up getting all 39 seats. INC, on the other hand, performed poorly.
Fresh elections were called when INC left the United Front government led by IK Gujral after it refused to drop the DMK from the government for its alleged link to Sri Lankan separatists responsible for killing Rajiv Gandhi. The result was a landslide victory for the NDA in TN, which helped Atal Bihari Vajpayee become the PM. J Jayalalithaa and the AIADMK broke off from their long alliance with the Congress and formed an alliance with the BJP by joining the NDA. This proved important in determining who the prime minister would be, since the AIADMK held 18 seats. That was short-lived, and the BJP lost the vote of confidence resulting in fresh elections.
A victory for the NDA, which won 26 seats from Tamil Nadu. After exiting from the NDA, AIADMK hoped to create some damage, but ended up losing eight seats. DMK allied with the BJP, helping them to power for the next five years.
A victory for the Democratic Progressive Alliance, which included the UPA and its allies (the Left Front). DMK and its allies were able to hold on to Pondicherry, which has one seat, allowing the UPA to win all 40 seats in the region. DMK won 16 seats, INC 10, PMK 5 and MDMK 4. The remaining 4 were won by the Left parties. Due to support of the Left Front for the government at the centre, all 39 seats in Tamil Nadu supported the formation of the UPA-led government.
There was a radical change in the alliances. DMK decided to stay with the UPA but the PMK, MDMK breakaway, and the Left parties decided to ally with the AIADMK and the newly-formed Third Front. After counting, results showed that DMK and its allies (INC and VCK) won a landslide victory, securing 27 out of 39 seats.
Between Modi and Jayalalithaa, TN chose the latter.
In an arguably larger Modi wave, TN (as usual) stands out alone, and fights the wave.