The 1977 Cubs contended for the NL East title for a good portion of the season. As I’ve noted many times, they hit 25 games over .500 in late June (47-22) and were eight games ahead in first place.
They had a bit of a shaky run in early and mid July, but maintained first place as they hosted the Astros at Wrigley Field for the last of a three-game series — the first two of which were a doubleheader in which the Cubs got swept. They led the division by one game going into this series finale.