Miami Marlins First-Place Eliminiation Scenario
Miami must win 23 more games (34 total) to avoid elimination from first place.
Here are the final standings in a scenario in which Miami finishes in first place with 34 wins:

Team             W	L	PCT	GB
Miami            34	128	0.210	0.00
Atlanta          34	128	0.210	0.00
Philadelphia     34	128	0.210	0.00
New York         34	128	0.210	0.00
Washington       34	128	0.210	0.00

Tie breakers
Miami wins the series with Atlanta 8 games to 5
Miami wins the series with New York 7 games to 6
Miami wins the series with Philadelphia 7 games to 6
Miami wins the series with Washington 7 games to 6

To construct the scenario, we start with the current standings in the division:
Team             W	L	GL	PCT	GB
New York         18	7	137	0.720	0.0
Philadelphia     13	12	137	0.520	5.0
Miami            11	13	138	0.458	6.5
Washington       11	13	138	0.458	6.5
Atlanta          10	14	138	0.417	7.5

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

Atlanta currently has 1 win(s) against Miami and 1 loss(es).
Atlanta wins 4 additional game(s) against Miami and loses 7.
Atlanta loses the series 5 games to 8.
Atlanta wins 0 additional game(s) against teams outside the division and loses 91.

Atlanta currently has 0 win(s) against New York and 0 loss(es).
Atlanta wins 9 additional game(s) against New York and loses 4.
Atlanta wins the series 9 games to 4.
Atlanta wins 0 additional game(s) against teams outside the division and loses 91.

Atlanta currently has 2 win(s) against Philadelphia and 1 loss(es).
Atlanta wins 0 additional game(s) against Philadelphia and loses 10.
Atlanta loses the series 2 games to 11.
Atlanta wins 0 additional game(s) against teams outside the division and loses 91.

Atlanta currently has 0 win(s) against Washington and 0 loss(es).
Atlanta wins 11 additional game(s) against Washington and loses 2.
Atlanta wins the series 11 games to 2.
Atlanta wins 0 additional game(s) against teams outside the division and loses 91.

Miami currently has 2 win(s) against New York and 4 loss(es).
Miami wins 5 additional game(s) against New York and loses 2.
Miami wins the series 7 games to 6.
Miami wins 0 additional game(s) against teams outside the division and loses 100.

Miami currently has 1 win(s) against Philadelphia and 2 loss(es).
Miami wins 6 additional game(s) against Philadelphia and loses 4.
Miami wins the series 7 games to 6.
Miami wins 0 additional game(s) against teams outside the division and loses 100.

Miami currently has 2 win(s) against Washington and 1 loss(es).
Miami wins 5 additional game(s) against Washington and loses 5.
Miami wins the series 7 games to 6.
Miami wins 0 additional game(s) against teams outside the division and loses 100.

New York currently has 3 win(s) against Philadelphia and 0 loss(es).
New York wins 10 additional game(s) against Philadelphia and loses 0.
New York wins the series 13 games to 0.
New York wins 0 additional game(s) against teams outside the division and loses 94.

New York currently has 0 win(s) against Washington and 0 loss(es).
New York wins 0 additional game(s) against Washington and loses 13.
New York loses the series 0 games to 13.
New York wins 0 additional game(s) against teams outside the division and loses 94.

Philadelphia currently has 2 win(s) against Washington and 1 loss(es).
Philadelphia wins 7 additional game(s) against Washington and loses 3.
Philadelphia wins the series 9 games to 4.
Philadelphia wins 0 additional game(s) against teams outside the division and loses 97.

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