The pre-poll alliance seems to be aimed at making the contest easy for Modi as the support by the Kurmis could prove to be a match-winner against his main rivals from Congress and Aam Aadmi Party in May 12 polls.
While Ajay Rai is the Congress candidate from this temple town, AAP has fielded its supremo and former Delhi Chief Minister Arvind Kejriwal against Modi.
Apna Dal, tagged infamously as a "game spoiler" due to its potential to divert votes in lakhs against a candidate, also has a significant presence in two of the five assembly segments here -- Rohaniya and Sevapuri.
Apna Dal has a significant presence in Rohaniya and Sevapuri.
The electoral alliance materialised only in the last week of March and Apna Dal, which resisted BJP's initial insistence on a merger, settled for two seats - Pratapgarh and Mirzapur - the latter being a constituency reserved for Scheduled Castes.
However, sources within BJP said that the long drawn-out efforts at the electoral tie-up had a lot to do with Varanasi, which has arguably become the most keenly-watched electoral battle across the country.
Anupriya Patel, Apna Dal's lone MLA and de facto leader, told PTI, "We will work hard not just for our own candidates but also to ensure the victory of Narendra Modi in Varanasi."
Anupriya, whose late father Sone Lal Patel had founded Apna Dal in the 1990s and evolved as the leader with maximum appeal among Kurmi voters of the state, said, "We can safely claim that our party will help in transferring no less than 1.5 lakh votes in favour of Modi."
Performance of various political parties in Varanasi in the 2012 assembly polls suggests that Modi would badly need this vote transfer if he is to win the seat with a margin commensurate with the hype around the contest.
Anupriya made her electoral debut from Rohaniya assembly seat in 2012, two years after her father died in a road accident, and won by securing over 30 per cent votes.
Incidentally, BJP finished fourth there, way behind BSP and SP, polling less than 10 per cent votes.
Another assembly segment where BJP put up a dismal show was Sevapuri, where Apna Dal did not win but managed to emerge runner-up with 20 per cent votes as against less than six per cent polled by the saffron party.
Both these assembly segments have a strong presence of Kurmis. As a matter of fact, Sevapuri was won for the SP by Surendra Patel, who was promptly rewarded by the party leadership with a ministerial post in the Akhilesh Yadav government.
However, for BJP, it was the second occasion on which it suffered a drubbing in these two assembly segments. In the 2009 Lok Sabha polls, party heavyweight Murli Manohar Joshi won by a modest margin of around 18,000 votes.
Analysts say the primary reason behind his lacklustre victory was the party's dismal performance in Rohaniya and Sevapuri where BJP had stood fourth.
Significantly, in both these assembly segments, Apna Dal's tally was significantly higher than that of BJP even though it trailed BSP and SP.
The electoral tie-up might ensure that the votes that might have otherwise gone to Apna Dal would shift towards BJP.
Anupriya dropped ample hints to the effect saying, "We will go to the people with the message that our tie-up with BJP is on account of the fact that Modi is an OBC leader and Apna Dal has always believed in the politics of social justice.
"Moreover, there is an obvious yearning for a change of regime and BJP being a big party would automatically be the most credible alternative. BJP under Modi's leadership is, therefore, the best bet."