In 2014, the SP patriarch contested both from Mainpuri and Azamgarh seat but chose to retain the latter after winning both. Mulayam defeated BJP's Shatrughan Singh Chauhan from Mainpuri by a huge margin of votes. Yadav received 5.95 lakh votes at 59.63 per cent vote share while Chauhan managed to get an estimate of 2.31 lakh votes at 23.14 per cent vote share.
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Later, Mulayam's grand-son Tej Pratap Singh contested against Prem Singh Shakya of BJP from Mainpuri in the by-election, where Shakya lost to Singh by approximately three lakh votes.
BJP and SP are the key parties contesting from Mainpuri seat. However, the Congress party has not fielded any of its candidate from this seat.
Mainpuri is one of the Lok Sabha seats that BJP failed to win or even challenge during the landslide triumph in the UP Assembly elections in 2017. The Congress had last won from Mainpuri in 1984.
This time, the 79-year-old leader has announced that it will be his last election and hence the party cadres and his supporters are hoping for a record victory.
Besides, Mulayam's last election, there is another change which has completely twisted the equation on the ground - the SP alliance with the Bahujan Samaj Party (BSP) , which has come as a big boost.
In 2004 and 2009, Mayawati-led BSP stood second here. But now SP and BSP, along with the Rashtriya Lok Dal (RLD), have come together to take on the BJP.
'Jiska jalwa kayam hai... uska naam Mulayam hai," is the rallying call of Mulayam's supporter in Mainpuri.
Caste equation is one of the decisive factors in the Yadav stronghold. Yadavs account for about 35 per cent of the total 16.53 lakh voters in Mainpuri, while the rest include Shakya, Thakurs, Brahmins, Scheduled Castes and Muslims .
The Mainpuri Parliamentary constituency comprises five assembly segments - Bhongaon, Jaswantnagar, Karhal, Kishni and Mainpuri.
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