1) Maharashtra was a stronghold of Congress for years until Shiv Sena took birth 2) Shiv Sena's approach to south INdians (during the 1970s) gave an impress to all other migrants that shiv sena is a regional and goodaism party - they lost continously for years. 3) with Gujarathis and other states imigrants, congress found it difficult to maintain their vote bank 4) BJP with their hindutva garnered strength and the imigrants vote split between BJP and congress non-shiv sainiks 5) To gain more mileage and to get in to power (state as well as centre) BJP joined hands with Shiv Sena and succeeded for one term. 6) Shiv Sena split - Uddhav - Raj - another split in shiv sainiks, locals 7) congress maintained the minority vote bank - muslims 8) with the growing imigrants of other states, shiv sena is losing ground day by day on vote bank - it is difficult for northies and southies to vote for shiv sena for what they have done against them in the past. and that too with the currtent situation of BJP sena going in for a divorce (e.g. Presidential election). 9) in short - Uddhav and Raj are losing grounds on politics and this is the only one way they can be in the limelight and gather local votes to be in power - after all Mumbai is a money minding machine for any politician.
the result: Shiv Sena will never ever get the votes of any imigrants in future. end of shiv sena in Mumabai