The three seats are Chanpatia, Chainpur and Kargahar.
The exit polls had predicted the strategist-turned-politician's party would draw a blank in its electoral debut.
As per the current trends, the ruling NDA is surging way ahead of Mahagathbandhan as the results are being declared on Friday.
As per latest update by NDTV, NDA- comprising Chief Minister Nitish Kumar's JDU and Prime Minister Narendra Modi's BJP- is leading in 146 seats.
Tejashwi Yadav's RJD-led Mahagathbandhan, which also comprises Congress, is leading in 73 seats.
The halfway mark in the 243-seat assembly is 122.
If NDA wins, Nitish will become the Chief Minister of the eastern state for the 10th term.
Bihar went to polls in two phases- on November 6 and 11.