You could do this a couple of ways. You could create a team containing all the "State Managers", then use JavaScript filters to pick the correct one dynamically. Or, if you have a way to access it you could assign it using their account in a variable.

For example, on one of my forms users make a task selection from a drop down, a lookup populates a hidden field with the AD account of the user responsible for that task, then on the business process side I assign the user task with the variable from the hidden field.