The White House’s favorite blogger posted an interesting nugget last night that has garnered a good deal of attention. Here’s what Marc Ambinder revealed about Gen. Stan McChrystal’s personal politics:

…Now it can be told. The story about him voting for Obama is not contrived. He is a political liberal. He is a social liberal. He banned Fox News from the television sets in his headquarters. Yes, really. This puts to rest another false rumor: that McChrystal deliberately precipitated his firing because he wants to run for President.

After Ambinder dramatically (now it can be told!) divulges that McChrystal is a political and social liberal who detests Fox News, he adds “yes, really” for emphasis. I’m far less interested in McChrystal’s domestic policy preferences than in the last sentence of that paragraph. Perhaps I’ve missed the boat, but I haven’t heard or read any credible rumors that even resemble what Ambinder reports. Apparently, we are to believe that serious people are peddling this tale: The erstwhile US and NATO commander in Afghanistan schemed to deliberately provoke his own dismissal in order to free him up to return state-side and run for president against Obama in 2012. Really? Had anyone heard those whispers prior to Ambinder announcing that his reporting can finally “put them to rest”?

If so, I stand corrected. If not, Ambinder appears to be debunking a theory no one has really advanced. Why?

As Team Obama’s go-to journoblogger, would it be unreasonable to conclude the White House may have wanted Ambinder to share this juicy partisan morsel with the world? My addled (or perhaps insufficiently Machiavellian) brain is struggling to solve the riddle of why.