I've done a tight connection at ORD before, mainline to american eagle. Luckily everything was in my favour (early arrival, 30+ minutes) and I was able to grab a quick bite before boarding my onward plane. Was lucky that I was in the same concourse and it wasn't a long walk.

AA offers these connections because they statistically have people successfully making them. If you're highly risk tolerant, i'd suggest taking the chance. It usually ends up with much better schedules than the other ones with long connections