The question is whether Palin's camp really believes Obama's behind it, or whether it's just politically useful to claim as such.
From Political Wire:
Jay Newton-Small, who interviewed Alaska Gov. Sarah Palin (R) for this week's Time magazine, notes that "one of the most interesting aspects of the story is how vehemently the Palin camp blames Barack Obama" for her troubles.
.... Palin aide Meg Stapleton said, "A lot of this comes from Washington, D.C. The trail is pretty direct and pretty obvious to us."
She goes on to argue that "the anti-Palin offensive seems lifted straight from The Thumpin', which describes the political strategies of Rahm Emanuel.