In a hand-delivered letter to the state GOP's executive committee Wednesday, John Sigler said he was resigning because of "newly emergent and totally unexpected circumstances" completely beyond his control.
Sigler says that because of the nature and origin of the circumstances he could not elaborate or comment further, except to say that the circumstances are not related to politics.
Sigler says in an email to The Associated Press that the letter speaks for itself and requires no further comment.
The decision caught state party leaders off-guard.
State GOP Executive Director John Fluharty says he is "stunned."