Mr Rai is listed as a director of Strategic Communications Laboratories (SCL) Pvt Ltd founded in 2011 as an Indian wing of SCL UK, the parent company of the data analytics firm accused of harvesting personal data from Facebook, Cambridge Analytica.
Alexander Nix and Alexander Oakes of the UK-headquartered SCL UK were directors of this company. Amrish Tyagi, the son of JD (U) leader KC Tyagi, was the fourth director of this firm, regulatory filings show.
At the time, Mr Rai and Mr Tyagi were already partners in another venture, Ovleno Business Intelligence (OBI), engaged in political management.
Reports that Cambridge Analytica may have worked with political parties in India have triggered a massive political row, with both the Congress and the BJP accusing the other of having used its services.
Mr Rai told NDTV that Alexander Nix did visit India in 2011, and began talks with him and Amrish Tyagi to extend SCL's operations into the Indian political scene.
They registered SCL India "to jointly prepare a database of Indian voters and manage the subsequent elections for potential political parties as clients," he said.
As Mr Rai tells it, Alexander Nix was keen to pitch the firm's services almost solely to the Congress, despite suggestions by the Indian partners to expand their roster of prospective political clients.
"One of the plans was to gift a database of 5 Lok Sabha constituencies to Rahul Gandhi, which included Gandhi family pocket boroughs like Amethi and Rae Bareli", he said.
The data collection was conducted by joint teams of OBI and SCL UK.
Records of internal meetings between Indian and overseas team members shared by Mr Rai suggests by late 2012, the pitch to the Congress had reached a fairly advanced stage.
Minutes of one such meeting held on 1 August 2012 was attended by Rajneesh Kumar and Richa Kumari from Mr Rai and Amrish Tyagi's team, and Sarah Ludecke from the UK team.
It refers to "INC client", to whom the team wanted to propose an idea of an "application/software" that would send text messages to INC members from Rahul Gandhi, a message most of the INC members were expected to respond to. This, according to the SCL team, would "allow the client to validate the authenticity of INC members' phone number in a low cost manner."
Later, the same document says, "The main client Mr Patel is dealing with Mr Amrish." Like the BJP, the Congress also claims they have had no dealings with Cambridge Analytica, or any of its related firms.
Increasingly, Mr Rai says, he and his team began to question the true motives of Alexander Nix's interest in the Congress.
"They (Mr Nix and his UK based firm) helped design a survey questionnaire which appeared to hurt the Congress even though we were pitching for a Congress contract. It relied heavily on questions on scams during the UPA era, even though it was supposed to be a pro-Congress survey", he said.
It implied that the parent company already had a client. She, however, didn't clarify on the identity of the client she was representing. Mr Rai couldn't recall her name.
Avneesh Rai claimed that when his team questioned her on the anti-Congress slant in the surveys, she said: "we are here to defeat the Congress".
"When I confronted Nix, he initially denied the allegation. Later, he said that 'I am here to make money', Mr Rai said. This, he said, was in 2012.
Alexander Nix, Mr Rai insists, refused to divulge the identity of the client.
Mr Rai said his association with Mr Nix, and with SCL ended soon afterwards.
The breaking point, he said, was a dispute over where the India data would be stored. He said he wanted it stored in India, with joint access to both the Indian and overseas partners. Alexander Nix, he claimed, disagreed. The client, he was told, wanted it stored in servers in the US.
Despite the parting of ways, all four directors remain on the corporate records of SCL India. Mr Rai claims that he has not been able to resign, since the Indian company was registered by Alexander Nix's chartered accountant. Since it has not filed returns since inception, its registration has been nullified according to new rules about dormant firms.
NDTV has sent a detailed list of questions to Cambridge Analytica about Mr Rai's assertions. A response is awaited.
Mr Rai also told NDTV that OBI, the firm founded by him and Amrish Tyagi, had done work for the BJP in 2012 UP elections.
He said the firm had supplied booth-wise age and caste data to the party. "We delivered it to the house of Sanjay Joshi (RSS functionary) who was then chief coordinator of UP elections for BJP. Narendra Singh Tomar (currently the Minister of Rural Development) was also present", Mr Rai said.
The BJP is yet to respond to these assertions.
Mr Rai denied suggestions that he was closely associated with the Samajwadi Party, whose campaign he was part of the in 2017 Assembly elections, claiming that his entire family supported the BJP. At a professional level, Mr Rai said he had helped with election strategy for all parties including the Samajwadi Party and the BJP.
OBI had featured the BJP, Congress and JD (U) as its clients on its website. But the BJP also has dismissed this claim, insisting that "thousands of websites had tried taking credit for BJP victory in 2014". The site has been suspended since Wednesday.