Salaried workers can receive overtime as well. Your thinking of exempt/non-exempt, which has more to do with responsibilities (e.g. management is an exempt category).

And the "political staff positions" are the in the same state bureaucracy as the other agency employees. They're not treated differently for retirement based solely on the fact that they work for the legislature.

And it's certainly possible to build up a lot of vacation and flex time (not strictly OT but it's still paid out at a reduced rate) in 6 years.