It was like Negative Voting. Anna did not compaign for any particular candidate and the aim was only to defeat the corrupt congress. Chautala stand second. Congress Third. It's quite evident that congress was only targetted. The trend might continue, if congress does not relent to public outcry, against corruption.
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Though his statement shows being adament, to some extent he is correct in the sense that congress candidate had no chance of winning even otherwise on local calculation. But, Anna factor is responsible for getting that high amount of votes both for Bisnoi and Chautala. Part of it would have gone to congress but for Anna factor.