Cincinnati Reds First-Place Eliminiation Scenario
Cincinnati must win 15 more games (61 total) to avoid elimination from first place.
Here are the final standings in a scenario in which Cincinnati finishes in first place with 61 wins:

Team             W	L	PCT	GB
Cincinnati       61	101	0.377	0.00
Milwaukee        61	101	0.377	0.00
Pittsburgh       60	102	0.370	1.00
Chicago          60	102	0.370	1.00
St. Louis        60	102	0.370	1.00

Tie breakers
Cincinnati wins the series with Milwaukee 7 games to 6

To construct the scenario, we start with the current standings in the division:
Team             W	L	GL	PCT	GB
Chicago          54	36	72	0.600	0.0
Milwaukee        51	40	71	0.560	3.5
St. Louis        48	43	71	0.527	6.5
Cincinnati       46	45	71	0.505	8.5
Pittsburgh       38	54	70	0.413	17.0

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

Chicago currently has 4 win(s) against Cincinnati and 2 loss(es).
Chicago wins 0 additional game(s) against Cincinnati and loses 7.
Chicago loses the series 4 games to 9.
Chicago wins 0 additional game(s) against teams outside the division and loses 45.

Chicago currently has 3 win(s) against Milwaukee and 2 loss(es).
Chicago wins 3 additional game(s) against Milwaukee and loses 5.
Chicago loses the series 6 games to 7.
Chicago wins 0 additional game(s) against teams outside the division and loses 45.

Chicago currently has 5 win(s) against Pittsburgh and 2 loss(es).
Chicago wins 0 additional game(s) against Pittsburgh and loses 6.
Chicago loses the series 5 games to 8.
Chicago wins 0 additional game(s) against teams outside the division and loses 45.

Chicago currently has 4 win(s) against St. Louis and 3 loss(es).
Chicago wins 3 additional game(s) against St. Louis and loses 3.
Chicago wins the series 7 games to 6.
Chicago wins 0 additional game(s) against teams outside the division and loses 45.

Cincinnati currently has 2 win(s) against Milwaukee and 5 loss(es).
Cincinnati wins 5 additional game(s) against Milwaukee and loses 1.
Cincinnati wins the series 7 games to 6.
Cincinnati wins 1 additional game(s) against teams outside the division and loses 44.

Cincinnati currently has 4 win(s) against Pittsburgh and 2 loss(es).
Cincinnati wins 0 additional game(s) against Pittsburgh and loses 7.
Cincinnati loses the series 4 games to 9.
Cincinnati wins 1 additional game(s) against teams outside the division and loses 44.

Cincinnati currently has 3 win(s) against St. Louis and 4 loss(es).
Cincinnati wins 2 additional game(s) against St. Louis and loses 4.
Cincinnati loses the series 5 games to 8.
Cincinnati wins 1 additional game(s) against teams outside the division and loses 44.

Milwaukee currently has 4 win(s) against Pittsburgh and 3 loss(es).
Milwaukee wins 2 additional game(s) against Pittsburgh and loses 4.
Milwaukee loses the series 6 games to 7.
Milwaukee wins 0 additional game(s) against teams outside the division and loses 45.

Milwaukee currently has 4 win(s) against St. Louis and 3 loss(es).
Milwaukee wins 2 additional game(s) against St. Louis and loses 4.
Milwaukee loses the series 6 games to 7.
Milwaukee wins 0 additional game(s) against teams outside the division and loses 45.

Pittsburgh currently has 5 win(s) against St. Louis and 4 loss(es).
Pittsburgh wins 4 additional game(s) against St. Louis and loses 0.
Pittsburgh wins the series 9 games to 4.
Pittsburgh wins 1 additional game(s) against teams outside the division and loses 46.

# Cincinnati Reds' magic number
# Cincinnati's magic number
# Reds' magic number
# MLB Playoff Race