Think of it as the game starts with the raiders having 12.5 point added already, and then you pick who would win if that is how the game started. This makes it so even if one team is expected to win by a lot it still would make sense to place a bet on an underdog.
Think of it as the game starts with the raiders having 12.5 point added already, and then you pick who would win if that is how the game started. This makes it so even if one team is expected to win by a lot it still would make sense to place a bet on an underdog.