HARRISBURG, PA (CBS) — A state House member from Montgomery County has become the latest Democrat to challenge incumbent Lt. Governor Mike Stack in next spring’s primary.

Madeleine Dean is just the latest to join a parade of Democrats doing something highly unusual – challenging an incumbent lieutenant governor of their own party.

Franklin and Marshall College political analyst Terry Madonna says it’s not a surprise, given the controversy that has surrounded incumbent Mike Stack.

But, Madonna says, what is noteworthy is the reluctance of Governor Wolf, a fellow Democrat, to wade into the race, given the widely-held perception that Wolf would prefer a different running mate next fall.

“He doesn’t run the risk of angering…major Philadelphia politicians,” Madonna said.

Madonna says Stack, a former state senator from Northeast Philadelphia, still has the support of some prominent Philadelphia Democrats, including Congressman and city Democratic Committee Chairman Bob Brady.