Bihar Chief Minister Nitish Kumar (right) with RJD chief Lalu Prasad.
The BJP, which will launch what it calls phase two of its Bihar campaign this week, assesses that Lalu Prasad and his Rashtriya Janata Dal will be its toughest opponent in the Assembly elections due by November and not Nitish Kumar.
Nitish Kumar, who made a comeback as Bihar Chief Minister in February this year, has "lost his USP," say BJP leaders and the party will focus it energies on attacking him. The BJP is eyeing the 100 constituencies that Mr Kumar's Janata Dal (United) will contest and which will have no Lalu factor.
The Nitish Kumar-Lalu Yadav-Congress alliance that the BJP takes on in Bihar has already announced seat-sharing - while the JD(U) and RJD will contest 100 seats each, the Congress will contest 40 and other minor partners three.
With Prime Minister Narendra Modi as the face of its campaign, flanked by leaders of allied parties, the BJP says it has reached 43,000 villages in Bihar in the first phase. In the second phase it plans to throw several questions at Nitish Kumar. Like, why he is partnering the Congress, a party he has fought since he was 17 years old. Or with Lalu Yadav, his most bitter rival for two decades. "Is he with Lalu today for Bihar's good or to be Chief Minister again," the BJP will ask.
The campaign for the high-stakes election has so far seen PM Modi direct a fusillade of barbs at Mr Kumar, who has responded in kind.
The PM has addressed two rallies in the state this month, using his last trip to announce a Rs 1.25 lakh crore package in central aid. The BJP hopes that will be the game changer in what is seen as a close contest.
For the BJP, Bihar is a must-win state. It had fought the last many elections as the junior partner to Nitish Kumar's JD(U), which ended the alliance two years ago. It is also the first state election after its debacle in Delhi at the hands of the Aam Aadmi Party.