Guess he forgot:
So when you combine the Bush tax cuts expiring, the sequester in place, the commitment of both myself and my opponent -- at least Governor Romney claims that he wants to reduce the deficit -- but we’re going to be in a position where I believe in the first six months we are going to solve that big piece of business.
It will probably be messy. It won’t be pleasant. But I am absolutely confident that we can get what is the equivalent of the grand bargain that essentially I’ve been offering to the Republicans for a very long time, which is $2.50 worth of cuts for every dollar in spending, and work to reduce the costs of our health care programs.
Emphasis mine. That quote would be from his off-the-record then on-the-record interview with the Des Moines Register. An interview he did the morning after the debate.
As Jim Geraghty pointed out four years ago, all Obama promises come with an expiration date. This one came with the half life of Potassium 42.
(H/T: Instapundit via a few other places)