Modi, in his third term as Gujarat chief minister, is contesting his first Lok Sabha elections from Varanasi and Vadodara in Gujarat. Rai, a Congress MLA here, has also been a BJP member in the past.
He had lost the Lok Sabha elections in 2009 when he had fought as a Samajwadi Party candidate. Exuding confidence about defeating Modi and others in the fray, including Aam Aadmi Party leader Arvind Kejriwal, he said he would eventually emerge as a "giant killer" as people of Varanasi want someone from among them to get elected and work for their welfare.
"I think Modi has been an MLA for three terms while I have been an MLA for five straight terms, including a byelection. This way, I am in fact senior to Modi by two terms when it comes to electoral politics," Rai told PTI in an interview.
Rai, who has been in active politics for over 18 years in the Varanasi area, also rejected any "Modi wave".
"There is no such (Modi) wave. Had there been a Modi wave, BJP would not have tied up with Apna Dal (a regional party with a strong backward caste base). You win all seats on your own in a wave. The tie-up with Apna Dal itself proves there is no wave," he said.
BJP has entered into an electoral alliance with Apna Dal, which is said to have a strong presence in the Purvanchal region, which includes Varanasi and adjoining areas.
Rai, whose family shares an old rivalry with local Muslim strongman Mukhtar Ansari, also dismissed talk about any behind -the-scene rapprochement with the latter's Qaumi Ekta Dal.
He has alleged that BJP has sealed a pact with Ansari in the last elections and said this time also, BJP should clarify its position vis-a-vis the minority leader.
In the 2009 Lok Sabha polls, BJP's Murli Manohar Joshi had defeated Ansari by a small margin, while Rai had come third.
Ansari had then fought on a BSP ticket and Rai was Samajwadi Party nominee. Later, Rai joined Congress and is currently an MLA from Pindra, while Ansari is also an MLA from Mau in Eastern Uttar Pradesh.
Ansari, currently in Agra jail, had earlier said he would contest the 2014 elections against Modi, but later withdrew his plans, saying he does not want anti-Modi votes to get divided. He said he would support the strongest candidate against BJP's Prime Ministerial nominee.
When asked whether he would request senior party leaders such as Sonia Gandhi, Rahul Gandhi and Priyanka Gandhi to come to Varanasi to campaign for him, Rai said, "All the senior leaders would come here. Many top leaders from across the country are about to come here.
"Priyanka Gandhi has said that she is not going anywhere except Amethi and Rae Bareli, but still I have requested her. I've told the party's top leaders they must come to the city of Lord Mahadev," he said, adding that all, including Sonia and Rahul Gandhi, have been requested to campaign here.
"Anyway, Varanasi elections are in the last phase on May 12 and, by that time, all leaders would be relatively free to come here," Rai said, adding that Union commerce minister Anand Sharma will be there when he files his nomination tomorrow.
Asked whether his nomination by Congress was delayed and if that had adversely impacted his campaign, Rai dismissed these apprehensions saying he was a "local" in Varanasi with a strong support base and it does not matter whether the announcement was made early or late.