Rick Santorum has a problem. Besides receiving more money from lobbyists than any other Senator (”We’re number one!”), being the most unpopular Senator in the land (”We’re number one!”), and being named after that unfortunate substance that Dan Savage just won’t let us forget (”We’re number two!”), he’s got a big problem in his traditional base of support, Western PA. Witness an editorial in today’s Pittsburgh Post-Gazette pointing out Radical Rick’s new problem:

Before every election, the Post-Gazette routinely sends letters to the candidates seeking material for the Voters Guide. Back in March, as part of that process for the primary, the newspaper sent a letter to Rick Santorum at his home address, at least the one that he claims. Back from Penn Hills came the letter with a sticker from the U.S. Postal Service checked as “Not Deliverable As Addressed — Unable To Forward.”

That is all you need to know about the nasty dispute between the Republican Sen. Santorum and his Democratic opponent, Bob Casey Jr., in the November election. The whole thing is rooted in one inconvenient fact for Sen. Santorum: He doesn’t live here anymore.

Somebody is going down.