WORD PROBLEM

If I understand correctly from a number of articles, John McCain's principal contribution to the bailout effort has been to "work the phones."

But now I see (via Bill Kristol at The Weekly Standard) that Douglas Holtz-Eakin of the McCain campaign is complaining that, in the crisis, Barack Obama "phoned it in."

Um, I've only been speaking English for forty-some years, so maybe I'm just not attuned to the nuances here, but can someone please explain to me what "working the phones" constitutes that "phoning it in" doesn't, given the fact that in this case both seem to involve the actual use of the telephone? And can someone explain to me why one is good and the other is bad?