National parties have to be more accomodative, then regional parties will merge with them, and regional satraps will get sidelined.
For that, we need truely national democratic party. Presently, there is only one, BJP.
Congress is not national party, its monarchy which inherited control over large part of the nation.
Congress monarchy have to go, then only another true national democratic party can born. Congress monarchy is the root cause of rise of regional monarchies.