1.In 1984-85 General Elections Indian national Congress won 414 seats* out of 533 seats in the leadership of Rajiv Gandhi Guided by Wave of Empathy(Due to Indira gandhi Assasination) is largest Victory by Any party in History of India.
*50% seat share and Majority Bieng(half of total seats )267
2.Indira Gandhi is the only Prime Minister till date who has lost a Lok Sabha election, while still in office. In 1977, she lost from Rae Bareli by a margin of 55,202 votes against Rajnarayan.
3.The largest victory margin in a Lok Sabha election is around 6 lakh (5,92,502 to be precise). Anil Basu of CPM defeated BJP candidate Swapan Kumar Nandi in 2004 Lok Sabha election by this huge margin in Arambagh constituency in West Bengal
4.The smallest victory margin in an assembly election is 1 vote and there are two candidates who hold this record. Most recently, CP Joshi, lost to BJP candidate Kalyan Singh Chauhan in Nathdwara constituency in Rajasthan in 2008 assembly elections by just one vote. His mother, wife and driver did not turn up to vote on polling day.
Neena Verma of BJP too had won by 1 vote in 2008 from Dhar, MP.
In karnataka AC election 2004, at Santhemarahalli candidate Dhruvanarayana R also won by 1 vote.
5.Rajiv gandhi won its election from amethi against Maneka gandhi in 1984-85 by margin of 83.7% share which is still record.
6.the highest victory margins since 1962 have ranged between 1,57,692 votes (polled by Gayatri Devi from Jaipur in 1962) and 5,92,502 votes (polled by Basu). On the other hand, the smallest margins range between 9 votes and 317 votes, the latter recorded by Namo Narain of INC from Tonk-Sawai Madhopur seat in 2009.