It's the most wonderful time of year.  It also happens to be the time of year when the names of possible Pennsylvania gubernatorial candidates are bandied about.  The latest politician considering challenging Governor Tom Corbett?  Montgomery County Commissioner Bruce Castor.

The stream of potential Democratic candidates weighing a run for Pennsylvania Governor is no surprise.  But the entrance of a serious challenger in the Republican primary would be an interesting development, says Muhlenberg College political science professor Chris Borick.

"There is a perception that Governor Corbett right now is wounded as a political figure and therefore vulnerable to a political challenge both in a general election and in the primary," said Borick.  "If you look at the Governor's public opinion polls over the last six months or so they clearly are in a range that points to significant liabilities."

Still, Borick says, it's unusual for an incumbent Pennsylvania Governor to feel a real challenge from within his own party.  In fact, "since the 1970's when Pennsylvania allowed governors to run for re-election we've seen each incumbent that has attempted to be re-elected, succeed."

A Castor-Corbett primary battle could leave Republican voters feeling like the really pretty girl at the school dance.  Borick points out that Castor would try to suck suburban Philadelphia support away from Governor Corbett, who has roots in Western Pennsylvania.