Congress can't win election anymore whether it's central or state. It's a clear gameplan to divert People of India to a sensitive issue. Nothing more than that. After latest Karnataka and other state elections they're sure they can't win, and hence saying now they'll go for the deal. If they win the Trust vote they'll get appeal to the People that they got something big for them, even if they loose also, they'll say, for India's prosparity, they sacrificed the Govt. and say BJP & Left had pulled down tahem.
