First of all, you need to understand that Indian politics is so flexible that it can go in all possible way and how much analysis you do ultimately what matters is the public sentiments and their vote. Before coming to your answer I would point one thing for all political parties that the parameter of governance and way of doing politics is deteriorating day by day which needs to fixed.
See I don't support any political party or ideology so will do a true analysis for your support.
I think there will a tough competition this time for BJP as they are in government in MP for almost 15 years which is something more than enough time. So now people will judge their performance not their promises whereas Congress will be enthusiastic about all sorts of promises they don't need to show the report card of their government. Another thing that dwells in my mind is the farmers which will be acting as a catalyst in coming elections, you would have heard about mandatory Kisan Aandolan against the government where they were retaliating against government policies and many farmers were killed. One thing is for sure that farmers there are not in the support of the present government and Congress would be taking this into a note. One thing that goes with BJPs is their Cm Shivraj Singh Chauhan who is a popular and known politician their and it will be an edge for BJPs another person who could add to it is the Pm itself his charismatic aura can really turn the way around for BJPs.
If you go into the history of Rajasthan, politics there is a chaos of government from so long, no government is still or could sustain its ability for more than one consecutive term. At present, there is BJPs government in Rajasthan so it would be challenging for them to sustain their government for another term. Moreover, there are media reports about differences between Amit Shah and Vasundhara Raje which is not a healthy situation for BJPs. So I will give more chance to Congress in Rajasthan. But again not to forget about Modi magic he has proved it many times and can prove it further. But on field and status, Congress gets more chance from me in Rajasthan.
Hope you could get it.