Ensconced in the DMK’S headquarters after packing off M.K. Alagiri, insiders swear the party’s 89-year-old patriarch M. Karunanidhi and his favoured younger son M.K. Stalin are now focused on just one thing— trouncing Union Finance Minister P. Chidambaram in Sivaganga, the Lok Sabha seat he narrowly won in 2009. Why? Because they hold Chidambaram singularly responsible for the DMK- Congress break-up.