PATNA, April 8 -- Ahead of Bihar assembly polls due later this year, leader of opposition in Lok Sabha and Congress leader Rahul Gandhi once again tried to win over the backward communities by saying that they do not have proportionate representation in the political, institutional and corporate sectors and made a strong pitch for a nationwide caste census and increase the cap on reservation if the party comes to power. He also put to rest all speculations on problem in Mahaghatbhandhan (Grand Alliance) in Bihar by announcing that alliance would contest assembly polls unitedly....