Congress has messed up so much in this country and at so many levels and for so long that it should actually be an advantage for BJP. It can leverage on all these pseudo socialistic policies and inefficient governance in the name of rural development and now "social inclusion". But it's not so easy. It needs a certain level of awareness at the lowest level of society. It requires people to understand how economy works and what opportunities exist if the markets are opened up and the governance is made more efficient. Again, it's not so easy. Each community needs to understand what is there for them in it and what are they missing now and why. BJP will have to sell this dream. In fact, it will have to not only sell it but make them realize how the current systems and policies are doing just the opposite. E.g. how NREGA is counter-productive and is doing more harm to economy than good. Instead building of roads, land reforms, and better irrigation, storage and transportation facilities will facilitate more earning and develop villages into towns and eventually cities. The party will have to develop a road map to implement these initiatives. Big work. How will it accomplish this? Where are the resources? I can't answer that. But if BJP has to survive, it will not only have to survive but also kill the competition.
Second issue is Hindutva. We all know BJP is in process of defining its Hindutva ideology and its taking forever. The trick is to also define the Congress' version of secularism up against Hindutva. Again, not only define but draw a picture of what's in it for everyone. It may have to go one step ahead and articulate how Hindutva is not a religious concept but more than that. It will have to clearly define what Hindutva includes and what it does not include. Needless to say, religious fanatism will have no place here. BJP will have to redefine the principle of Hindutva to mean libertarianism, progress and an Indian Society that works towards a goal; to make India what it should be, strong and prosperous India. The timing for BJP is most opportune to accomplish this. It has lost two elections back to back. There is need to revive the party in a new way. It can easily do away with ideologies that didn't work for it.
You might argue that the party can't just do away with its core principles. Here I want BJP to learn from the Congress. No matter what Congress does, it plays excellent politics. That's what BJP will have to do. And it will all be for a good reason.