Elections 2019: Lucknow is also one of the rare seats where the Congress has always done well. (File)

One of the key constituencies in what is now looking like a three-cornered fight in Uttar Pradesh for the national election, due by May, is the state's capital Lucknow. For decades, the seat has been a BJP stronghold with stalwarts like Atal Bihari Vajpayee and now home minister Rajnath Singh as its representatives in parliament. Interestingly, it is the Congress that is the BJP's main opponent on the seat.

This Lok Sabha seat, with a significant Brahmin-Thakur vote, has seen a non-Brahmin MP only four times since 1951. Lucknow has also been a BJP stronghold for over 25 years now. It was represented by former PM Atal Bihari Vajpayee, a Brahmin, from 1991 to 2009; current Bihar governor Lalji Tandon, a Khatri, in 2009; and Home Minister Rajnath Singh, a Thakur, from 2014.

Lucknow is also one of the rare seats where the Congress has always done well. The party won the seat seven times since 1951 and was number two in 2009 and 2014. In 2014 - the Congress fielded then party leader Rita Joshi, a Brahmin, against Rajnath -- who was contesting from Lucknow the first time. In the sweeping Modi wave, Rajnath Singh polled double the votes of Rita Joshi. His vote share -- 54 per cent, was also double that of Rita Joshi's at 27 per cent.

Congress sources, however, say 2014 was an unusual election because of the Modi factor; the 2009 contest on the same seat was much closer, with the BJP's Lalji Tandon polling a little over 2 lakh votes and Rita Joshi collecting 1 lakh 63 thousand.

The Congress has more than one problem in Lucknow. Its star candidate Rita Joshi is now with the BJP and also a UP minister and the party is still looking for a replacement. This has led to some unusual demands at the Congress headquarters in Lucknow - where Priyanka will sit as the Congress's eastern UP in-charge.

"Many people are vying for the seat but I would like to request Priyanka Gandhi to contest from Lucknow; it will be a 'balle balle' situation for us and then Rajnath Singh or even Modi won't know what hit them," said Vinod Chaudhary, a former Congress legislator from Lucknow.

"Rajnath Singh fought an election against me too. We both lost to a third candidate. He does not have a very big standing. It's just that the Congress's graph in Lucknow had fallen but today, we are all set," he claimed.

The BJP has a counter. "See, in a three-cornered fight, the BJP will benefit. Lucknow was Atal Bihari Vajpayee's constituency and his good work has been carried on by Rajnath Singh. We are not worried anywhere. Even in Amethi and Raebareli. They (Congress) should worry about those seats and forget about the rest," said Sameer Singh, a BJP leader.

Making an impact on the Lucknow seat seems tough for rivals-turned-allies Akhilesh Yadav and Mayawati. None of the two have ever won this Lok Sabha seat, but sources in both Akhilesh Yadav's Samajwadi Party and Mayawati's BSP say they are very much in the game. The 2014 polls were a disaster for both parties in Lucknow with a joint vote share of just over 11 per cent. But the 2009 polls were far more interesting - the two had a joint vote share of 32 per cent, second only to the BJP.