Yesterday Battle ‘10 reported on the planned departure of Scott Fairchild, Rep. Pat Murphy’s (D-8th) chief of staff, and the man who engineered his 2006 election to the House. Fairchild has begun to advise Rahm Emanuel on his bid to become Chicago’s next mayor in that city’s February 2011 election.

Murphy beat out then Rep. Mike Fitzpatrick by fewer than 1,500 votes, or about two percentage points. Current polling has Fitzpatrick leading Murphy by 14 points, according to the latest Franklin & Marshall poll, which leads to speculation about the cause of Fairchild’s planned departure.

Some see this as a sign that Fairchild simply wants to move on and diversify his career after four years in Pennsylvania, while others speculate that it could be a sign that Fairchild believes he’s done all he can for an unpopular incumbent.

Fairchild, for his part, will formally stay with the Murphy campaign through Election Day.

“Chicago certainly is Patrick Murphy’s kind of town,” Fitzpatrick communications director Darren Smith told Battle ‘10. ”He’s raised tens of thousands of dollars there.”

Smith suggested that Fairchild could be “more interested in Chicago politics than working to create jobs in Bucks County.”

Rep. Pat Murphy’s campaign did not respond to a request for comment.