Or another way to look at it, the cubs only have 39 more games. It's as likely the cubs catch the cards as the giants catching the cubs. Giants have 3 more shots at the cubs. The cubs have 6 more games vs both the cards and the pirates. If the cubs take 4 of 6 from the cards the chase gets a lot more interesting.
In fact other than a lone game against KC, the cubs schedule is pretty weak. They have the SF series, the LAD series, 2 vs the pirates and cards but then they play philly in a 4 game, CIN twice, AZ, and MIL twice. AZ is about .500. CIN, MIL and Philly are 3 of the 5 worst teams in baseball.