In my opinion, all the constituents of UPA will have to fall in line with the whip of Congress. When B .J. P / S.A.D won Punjab elections this year, the West Bengal Chief Minister decided to attend the swearing in ceremony of the SAD CM. The second biggest constituent of UPA thought, it would send a shock-wave to Congress. But in stead, the Congress spokesperson Abhishek Manu Singhvi reminded TMC of the Laxman Rekha. the program was cancelled and it was decided to send another minister. It proves that the brave words of the partners are just gallery show and was within the tolerable limit of the big brother. But when one crosses too far, he/she would be shown red eyes and their braveness would disappear.
But the BJP have no such authority over their partners while in opposition. So if there is any cross voting, NDA will be the sufferer.
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Sir in politics there are no permanent enemies or bedfriends - it changes by the minute or else how could Dimple Yadav win unopposed in UP, - its just that both the Congress and NDA wants to keep Mulayalam in good spirits, for the future - read 2014