Tamil Nadu election history shows important changes in the voting system and schedule over time.
The 1967 election was a major turning point as Dravida Munnetra Kazhagam defeated the Indian National Congress, and seats increased from 206 to 234 after delimitation.
The 1971 election was held over three days, but in 1977 all 234 constituencies voted on a single day for the first time.
Despite this, the State returned to a two-phase election in 1980, and the 1984 election was the first to be held at the end of the year instead of in the summer.
The 1996 election was the last with ballot papers; in Modakurichi, voting was held on June 1 due to 1,033 candidates making printing difficult.
Electronic Voting Machines were first used in all 234 constituencies in 2001, also in Kerala, Puducherry, and West Bengal.
The 2011 election had the longest gap between polling (April 13) and counting (May 13) due to a multi-state schedule by the Election Commission of India.
In 2016, voting in Aravakurichi and Thanjavur was postponed for the first time due to large-scale voter bribery.