With Mallikarjun Kharge set to become the Congress president, former finance minister P Chidambaram and Digvijaya Singh are in the race to succeed him as leader of opposition in Rajya Sabha, with Singh's nose seemingly ahead.With Mallikarjun Kharge set to become the Congress president, former finance minister P Chidambaram and Digvijaya Singh are in the race to succeed him as leader of opposition in Rajya Sabha, with Singh's nose seemingly ahead.