The party stopped short of formally declaring him their candidate for the country's top job, but the message was loud and clear.
Party president Rajnath Singh garlanded Modi after singling him out as the "most popular" of the BJP's five chief ministers, and asked for a standing ovation saying: "Words and claps are not enough to welcome him."
Delegates stood up, clapped and whistled, and the other CMs - some of them potential rivals for the PM candidature - shook hands with the charismatic but controversial figure.
Not originally in the Modi fan club, Singh has been increasingly promoting the leader in recent weeks, possibly to align himself with the wishes of the rank and file.
He termed Modi's election win in Gujarat "historic", noting that "even on the global stage, he has been praised".
Modi is due to speak on Sunday and could use the event to send a message of intent.
The first step in his elevation could be membership of the BJP's parliamentary board, which includes heavyweights like LK Advani, Sushma Swaraj and Arun Jaitley.
The buzz at the event was that this could happen when Rajnath reconstitutes the body later this month.
But going from being the BJP's posterboy to the candidate of the BJP-led National Democratic Alliance (NDA) could be a rocky ride.
A key BJP ally, the Janata Dal (United), led by Modi baiter and Bihar chief minister Nitish Kumar, reiterated its stand that the NDA as a whole would take a call on who would be the alliance's PM candidate.
"If he's won a third term, it's natural that he's being hailed by the national council. But we've made our position on the matter clear," Shivanand Tiwari, JD(U) Rajya Sabha MP, told HT.
The JD(U) is opposed to Modi due to his alleged role in the 2002 riots in Gujarat in which many Muslims were killed.
Earlier, those approaching the venue of the conclave were greeted by placards reading "Modi laao desh bachaao (bring Modi, save the nation)".
As Delhi BJP chief Vijay Goel stood up to welcome the delegates and kickstart the proceedings, he said, "It seems as if Manmohan Singh isn't the prime minister; it seems as if Narendra Modi is the PM. No decision has been taken yet, but people wish that Modi becomes prime minister."
While former finance minister Yashwant Sinha has openly backed Modi for PM, senior leader Jaitley has also said there is "growing interest" in Modi as PM candidate.
On Saturday, BJP women's wing chief and regular on TV talk shows, Smriti Irani, endorsed his possible candidature.
Rajnath Singh in his speech dealt at length with somewhat hardline themes that signaled a reaching out to the party's Hindutva roots.
He focused on the UPA's "failures" on internal and external security and demanded the deportation of illegal Bangladeshi immigrants.
He also defended Hindutva, recalling that the Supreme Court had upheld it as a way of life and adding that it was Hindus who had embraced the belief 'Vasudhaiva Kutumbakam' (the world is a family).
He also made a pitch for throwing out the ruling UPA, accusing it of "economic mismanagement".