The Bears have a bad record but they aren't as bad as their record suggests. They've lost some close games and part of their issues revolved around bad QB play from Mike Glennon. Trubisky took over and looked much better, but it was a tough start against a very good Vikings defense.
Its worth noting that the Bears have had a brutal schedule. Every team they played so far is a playoff caliber team. Also, the Bears are 6th in defense and have a good running game. That combination leads to close games. Even on the road. They played a tight game with the Vikings last week, almost beat the Falcons.
The Ravens are a middle of the road team. They are 3-2. The Bengals game was well played, but their other wins included the Browns and Carr-less Raiders. They looked bad against the Jaguars and Steelers.
I just expect a close game. So the Bears will cover.