She has appeared on Broadway 8 times as part of the original cast. I am not sure about the size of her role (and therefore eligibility) in some of her earlier shows.
She was nominated 3 times out of her 8 appearances, and won 1 of the 3.
I gather she was probably ineligible for PUMP BOYS, PRELUDE TO A KISS, and NICK & NORA. We probably shouldn't mention COMPANY, and I didn't see AH, WILDERNESS.
But she WAS nominated for REDWOOD CURTAIN, PICNIC, and STEEL PIER.
I would say she has a pretty good track record. Considering her roles and their size (eligibility), she has probably been nominated about 50% of the time.
Regardless, based on out of town buzz, Monk is a lock.
"If you are going to do something, do it well. And leave something witchy."
-Charlie Manson