For Nitish and Laloo to come together and for Laloo to agree to declaring Nitish the chief ministerial candidate: these two developments have boosted Nitish' prospects, but it might still not be enough to take him past the finish line. This prevents a total wipeout like in the 2014 Lok Sabha elections. But if the BJP manages to rope in both Jitan and Pappu, both of whom are opposed to Nitish, it suddenly starts looking 60-40 or better for the BJP.
The wild card here is not who will ally with whom but respecting that all elections are about the future. What will Nitish do over the next five years? If he goes on the Give Me My Wages tangent like in 2014, he will lose, possibly decisively.
Nitish is more charismatic than Sushil Modi who still acts like he is trying to get away from under Nitish' shadow. Otherwise SuMo has a legitimate claim that he was crucial - indispensable - to Nitish giving seven excellent years as Chief Minister. It was the BJP that administered the road and health departments which showed some of the best work.
Sushil Modi should tell the people of Bihar what he will do over the next five years.
One of these two will become Chief Minister, the other will be Opposition Leader.
Another wild card is PM Modi. If he makes enough campaign stops, he will make a bad situation worse for Nitish. A victory in Bihar gives NaMo greater leg room in the Rajya Sabha, gives him a political boost nationally as he starts his second year, and brightens his prospects for Uttar Pradesh, a twice big a prize, and one that would cure all his Upper House woes. It is like NaMo needs the Bihar victory more than SuMo does. So expect him to campaign hard and make life miserable for Nitish.