Narendra Modi who will become the Prime Minister of India is expected to resign as the Gujarat chief minister on May 21 after a special state Assembly session. But there is still uncertainty on who will be his successor. Though revenue minister Anandiben Patel is the frontrunner. Modi can spring a surprise.With the Congress suffering a complete wipeout in the state in this year`s elections, Modi is now reportedly flirting with the idea of depriving the party of its last vestiges of support in Gujarat, the tribals, by appointing a tribal leader as his successor.And he has found a viable nominee in his state Forest and Environment Minister Ganpat Vasava (42).