Ever since he floated the All India Confederation of SC/ST Organisations in 1997, Udit Raj has become the most visible Dalit face in the country. The Indian Revenue Service officer's formula of mobilising educated Dalits has been enormously successful. His embracing Buddhism last year and subsequent mass conversion drives have given a major political spin to his movement. He speaks to Davinder Kumar about why conversion is the only political tool the Dalits have to fight for their rights. Excerpts: