"Bhagwat's statement on review of reservation for Dalits and OBCs harmed the NDA's prospects as it was made one of the main issues by the Grand Alliance," Mr Manjhi told the media in Patna.
Mr Manjhi said the issue of reservation in educational institutions and in jobs badly affected the Bharatiya Janata Party-led National Democratic Alliance (NDA).
He said Mr Shah's statement that firecrackers would be burst in Pakistan if the BJP lost the Bihar assembly polls also played a major role in the NDA's defeat. "The statement only helped the Grand Alliance."
Mr Manjhi's party contested from 20 seats but won only one seat.
The party's sole victor was Mr Manjhi himself. He won from Imamganj in Gaya, his home district.
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