CPM was well within their rights to withdraw support to the government. But after that they should have behaved like statesmen. Rooting for Mayawati as the next PM was an insane act of desperation. Mayawati just now gave an interview in which she said, the BJP and congress colluded to spoil her chances to become the first DAlit PM of the country. Apparently this was the promise that PRakash Karat gave her.