Election 2014 built up -1...nothing to imagine!

alliances will govern the government 

While Congress will be judged based on the alliance it keeps, BJP will be judged on alliance it seeks.

Congress can't escape some alliance, they are too inter-connected, it can't rely on a few others, those who have high stakes to remain in power will desert if they sense Congress is a sinking ship; those that know Congress will need them badly will seed bigger favours.

BJP is driven by an ambitious man, who wants to be PM, they are more likely to compromise on principles for numbers (meaning votes) in seeking alliances. They would want some alliances rather bad, and those who know that will seek large bargains which BJP is in no position to reject; the party may have to retain some alliances out of loyalty to partners who have stuck around for long at the cost of some newer alliances.

strategies people (do / will / are likely to) play

Most regional parties will try and retain their stronghold at whatever cost so as to be able to drive a better bargain at the national level. those in power will do so through coercion, persuasive policies, doles and defaming and ensuring that there are cases against the opposition. Those not in power will try regular tactics, buy small pockets of votes from smaller leaders who can trade on votes, they will realign smaller parties to ensure that split votes cause their victory at least in a few seats if there is an unfavourable condition for themselves.

Congress can play the tough moral card, as it realizes morality is what it lacks completely; it could compromise all the partners who have tainted image, seek a makeover, re align with newer parties and  lose the election, but, gain moral high ground. however, this will effectively see several local splits and even desertion at the national level. eventually if it retains its cadre, it may regain power in a couple of years with more strength if it adopts such a stature, but, the people and courage to do that is not there (though Rahul Gandhi could).

BJP may play the tough card in seeking alliance, however, everyone knows that except for one carefully built image, there are not many mass leaders in the party, definitely at the national level. so for BJP to  play tough will be the most difficult situation. they may fall victim to several regional manipulations as long as it suits their quest for numbers, in these compromises for numbers now will be the seeds of seat sharing and alliance of corruption later on, eventually it will realize it can't govern any better than the Congress with such alliance.  but, it may not have the wisdom to deny such difficult alliances.

numbers will unite and split as well

The numbers of the collective may be counted as the basis to form the government, however, it would also ensure that the government can't do much as there will be people with smaller and smaller principle base and larger short term money base who will be 1-unit coalition members. it will be each on for themselves and many more will be seeking return of investments and this can only lead to more corrupt times. 

Cost of elections will go up this time, far more people are likely to seek money for their votes than ever before as there is a general feeling that every political party has money that they don't declare and there may be enough to go around for all. however, the disbursement of money may not have any relevance to who gets voted or booted, after all it is a secret process.

peace will suffer

Elections may also be violent as more and more people with better knowledge of the locality and no care or comprehension of the centre will be fighting in their own turf, several turf wars of the area will come to be played out.

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