It can definitely be a comfortable lifestyle on a budget, but it is by no means rich. Housing costs alone makes it blatantly middle class. Add in kids which brings it own costs, and saving for college, which is basically a 2nd mortgage if you save what you're supposed to, and that income range is just getting by like everyone else
They just might have a bigger house, nicer cars, and can take better vacations. But they are busting their ass for those slight luxuries.