If a player bets (with players behind him still in the hand) and is raised by an all in player, with callers in between can the original better re-raise above the all-in?

It depends. If the all in player's raise constitutes a full raise or not. If it does, then he can re-raise. If not, he can only complete the bet.Ex. Blinds 50/100. Player A bets 200, Player D goes all in for 250. Player A can only call the extra 50. On the other hand if Player D goes all in with 300 or more, then Player A can re-raise as the All-in constituted a full bet.