Miami Marlins First-Place Elimination Scenario
Miami must win 24 more games (46 total) to avoid elimination from first place.
Here are the final standings in a scenario in which Miami finishes in first place with 46 wins:

Team             W	L	PCT	GB
Miami            46	116	0.284	0.00
Atlanta          46	116	0.284	0.00
New York         45	117	0.278	1.00
Washington       45	117	0.278	1.00
Philadelphia     45	117	0.278	1.00

Tie breakers
Miami wins the series with Atlanta 8 games to 5

To construct the scenario, we start with the current standings in the division:
Team             W	L	GL	PCT	GB
Atlanta          35	16	111	0.686	0.0
Philadelphia     25	25	112	0.500	9.5
Washington       25	26	111	0.490	10.0
New York         22	28	112	0.440	12.5
Miami            22	29	111	0.431	13.0

Next, we show how the remaining series of games plays out in the scenario:

Atlanta currently has 5 win(s) against Miami and 2 loss(es).
Atlanta wins 0 additional game(s) against Miami and loses 6.
Atlanta loses the series 5 games to 8.
Atlanta wins 0 additional game(s) against teams outside the division and loses 76.

Atlanta currently has 0 win(s) against New York and 0 loss(es).
Atlanta wins 11 additional game(s) against New York and loses 2.
Atlanta wins the series 11 games to 2.
Atlanta wins 0 additional game(s) against teams outside the division and loses 76.

Atlanta currently has 5 win(s) against Philadelphia and 1 loss(es).
Atlanta wins 0 additional game(s) against Philadelphia and loses 7.
Atlanta loses the series 5 games to 8.
Atlanta wins 0 additional game(s) against teams outside the division and loses 76.

Atlanta currently has 3 win(s) against Washington and 1 loss(es).
Atlanta wins 0 additional game(s) against Washington and loses 9.
Atlanta loses the series 3 games to 10.
Atlanta wins 0 additional game(s) against teams outside the division and loses 76.

Miami currently has 0 win(s) against New York and 0 loss(es).
Miami wins 6 additional game(s) against New York and loses 7.
Miami loses the series 6 games to 7.
Miami wins 0 additional game(s) against teams outside the division and loses 73.

Miami currently has 1 win(s) against Philadelphia and 3 loss(es).
Miami wins 2 additional game(s) against Philadelphia and loses 7.
Miami loses the series 3 games to 10.
Miami wins 0 additional game(s) against teams outside the division and loses 73.

Miami currently has 2 win(s) against Washington and 1 loss(es).
Miami wins 10 additional game(s) against Washington and loses 0.
Miami wins the series 12 games to 1.
Miami wins 0 additional game(s) against teams outside the division and loses 73.

New York currently has 0 win(s) against Philadelphia and 0 loss(es).
New York wins 8 additional game(s) against Philadelphia and loses 5.
New York wins the series 8 games to 5.
New York wins 1 additional game(s) against teams outside the division and loses 66.

New York currently has 3 win(s) against Washington and 4 loss(es).
New York wins 5 additional game(s) against Washington and loses 1.
New York wins the series 8 games to 5.
New York wins 1 additional game(s) against teams outside the division and loses 66.

Philadelphia currently has 2 win(s) against Washington and 1 loss(es).
Philadelphia wins 1 additional game(s) against Washington and loses 9.
Philadelphia loses the series 3 games to 10.
Philadelphia wins 0 additional game(s) against teams outside the division and loses 73.

# Miami Marlins' magic number
# Miami's magic number
# Marlins' magic number
# MLB Playoff Race