I had a flight come in a C22 (almost the end of the C concourse) at 6:50 last night, and leave out of A4 at 7:31. I'm a brisk walker, and I made it with about 10 minutes to spare. Granted my flight was supposed to arrive at 6:17, so it was a little late and the weather was a mess. I'd say if your flight comes in on time, or close to it, you should have no problem.

Oh, and it's Mesaba, not Mesa. Two VERY different companies.