A Bet for Pacquiao

I have read that after the recent win of Pacquiao over Cotto wherein a 3-1 betting is made ..Casino is already getting bets for Pacquiao over Mayweather even though a fight isn't yet announced... In the recent fight of Cotto and Manny Pacquiao , Arum reveals that the money coming from the sports book is Philippines . It seems like people bet for Manny . So how this going to change with Mayweather-Pacquiao fight will betting would be in favor of Mayweather or Pacquiao??. At this point this event will surely make sportsbook alive again