Cincinnati Reds First-Place Eliminiation Scenario
Cincinnati must win 14 more games (66 total) to avoid elimination from first place.
Here are the final standings in a scenario in which Cincinnati finishes in first place with 66 wins:

Team             W	L	PCT	GB
Cincinnati       66	96	0.407	0.00
Milwaukee        66	96	0.407	0.00
St. Louis        65	97	0.401	1.00
Chicago          65	97	0.401	1.00
Pittsburgh       63	99	0.389	3.00

Tie breakers
Cincinnati wins the series with Milwaukee 8 games to 5

To construct the scenario, we start with the current standings in the division:
Team             W	L	GL	PCT	GB
Chicago          59	39	64	0.602	0.0
Milwaukee        58	40	64	0.592	1.0
Cincinnati       52	47	63	0.525	7.5
St. Louis        51	48	63	0.515	8.5
Pittsburgh       39	60	63	0.394	20.5

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 3 additional game(s) against Cincinnati and loses 4.
Chicago wins the series 7 games to 6.
Chicago wins 0 additional game(s) against teams outside the division and loses 37.

Chicago currently has 3 win(s) against Milwaukee and 2 loss(es).
Chicago wins 2 additional game(s) against Milwaukee and loses 6.
Chicago loses the series 5 games to 8.
Chicago wins 0 additional game(s) against teams outside the division and loses 37.

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 37.

Chicago currently has 4 win(s) against St. Louis and 3 loss(es).
Chicago wins 1 additional game(s) against St. Louis and loses 5.
Chicago loses the series 5 games to 8.
Chicago wins 0 additional game(s) against teams outside the division and loses 37.

Cincinnati currently has 2 win(s) against Milwaukee and 5 loss(es).
Cincinnati wins 6 additional game(s) against Milwaukee and loses 0.
Cincinnati wins the series 8 games to 5.
Cincinnati wins 0 additional game(s) against teams outside the division and loses 37.

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 0 additional game(s) against teams outside the division and loses 37.

Cincinnati currently has 3 win(s) against St. Louis and 4 loss(es).
Cincinnati wins 4 additional game(s) against St. Louis and loses 2.
Cincinnati wins the series 7 games to 6.
Cincinnati wins 0 additional game(s) against teams outside the division and loses 37.

Milwaukee currently has 4 win(s) against Pittsburgh and 3 loss(es).
Milwaukee wins 1 additional game(s) against Pittsburgh and loses 5.
Milwaukee loses the series 5 games to 8.
Milwaukee wins 1 additional game(s) against teams outside the division and loses 37.

Milwaukee currently has 4 win(s) against St. Louis and 3 loss(es).
Milwaukee wins 0 additional game(s) against St. Louis and loses 6.
Milwaukee loses the series 4 games to 9.
Milwaukee wins 1 additional game(s) against teams outside the division and loses 37.

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 2 additional game(s) against teams outside the division and loses 38.

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