If a team is -8 in NFL betting at BetMGM, they're favored by eight points. Their opponent, the underdog, would be +8.
To cover the spread (-8), the favorite must win by at least nine points. If they win by exactly eight points, it would be a push.
To cover the spread (+8), the underdog must lose by seven or less points, win the game, or tie (after overtime). If they lose by exactly eight points, it's a push.
Overtime is included in the final score that determines if the team covers the spread.