Amar Singh and Mulaiam Singh will go to suport with Sonia on N-Clear but why they are ready?

Now its head line that Amar Singh and Mulaiam Singh are ready to suport to congress party head Smt Sonia Gandhi at any cost and its confirm while Left already warned to govt to withdraw the suport. and some time before Amar singh and Mulaiam singh were against to congress but now what is fear to them to suport at any cost to congress Chief Smt.Sonia Gandhi