Ever since RSS chief Mohan Bhagwat's comment came on the need to have a rethink of caste-based reservation, BJP knew it was doomed. What did the party not do to reverse the damage these comments had done - from BJP distancing from his remarks to assuring the people of Bihar that it would name an OBC as their CM after the elections - but the irreparable damage had already been done. If this was not enough, Union minister VK Singh did a ‘Mohan Bhagwat’ too and in fact very soon. “The government cannot be held responsible if a stone is thrown at a dog,” he said on the murders of two Dalit children in Faridabad. And pat, there went the Dalit votes to the grand alliance’s kitty. Muslims weren’t happy with BJP too with Dadri lynching incident, the remarks by BJP leaders that followed and the entire row over beef eventually assuming focus in the public discourse. It all went against the saffron party with Nitish and Lalu motivating Muslims to not vote for the BJP. Moreover, Asaduddin Owaisi's All India Majlis-e-Ittehad-ul Muslimeen (AIMIM) was supposed to play a crucial role to mobilize voters but it failed drastically with the votes going in favour of the grand alliance ultimately. So much about vote bank politics in a caste-dominated state polls.
Next comes Nitish’s face with Lalu’s base that did the trick for the two.
As these two strong personas were fighting it hard on the ground, they stood againt a national party no doubt, but one that lacked a strong local face to win the trust of voters on the ground. Modi was once again put on the ground to steer votes towards BJP, not realizing that a disinterested local leadership was always going to be a big disadvantage for the party. Adding to this, the weak allies the party had - Ram Vilas Paswan's LJP; Jitan Ram Manjhi's HAM and Upendra Kushwaha's RLSP – hardly managed to get anything for the BJP. It’s no surprise because they were weak contenders from the beginning.
All these factors coupled with a dieing Modi wave of course had very little in store for the BJP. It was but obvious, that Lalu-Nitish and their grand alliance had to have the last laugh!