How will the 2019 General Elections pan out?

Currently, the political scenario in the country suggests that the Congress will have to form an alliance with the biggest parties of all Indian states because taking on the BJP alone will be suicidal and detrimental to the future of the party’s national presence.

How do you think the General Elections will pan out in 2019? What will be the impact of regional parties such as AAP, SP, BSP, TMC etc.?