I am not sure how real is "floating voter" theory. Every party has a committed band of voters, who vote for the same party in every elections, come what may. Presumably there's a band of floating votes which changes results of every elections. It would be interesting to analyse the new votes added in every election & their pattern. There are two categories of new voters in India.First category consists of those who turned 18 before new elections. Second category off course is the new voters added from Bangladesh & Pakistan, most likely in states of Bihar,Assam,UP & Bengal. Analysing, floating votes, is a huge study in itself.
One theory which surely does exist is the one where the voter supporting the ruling party does not come out to vote at all.She's disenchanted with the present regime, but does not favour the opposition either.This theory can explain a lot of flip-flops.
