LUCKNOW, Feb. 21 -- The chink in the PDA (Pichada, Dalit, Alpsankhyak) armour of the Samajwadi Party (SP) widened when OBC leader Swami Prasad Maurya resigned from the party's primary membership and the Uttar Pradesh Legislative Council on Tuesday-a week after he quit the party's national general secretary post on February 13....