I worked part time in grad school with a long commute. That's the thing that's tough about it, because you've got to travel from work, to class, to home again. For me, it meant having to gobble dinner on the road in like 10-15 minutes, or else I wouldn't eat until 10pm.

If you can find a job on campus or at least very close to campus, you might have a much easier time, commute time and schedule are going to be some of your biggest challenges.