WaPo thinks so.
Actually, he's been out for quite some time. He needed to win in Iowa, and he faded badly from a clear front-runner's position there last year to a dismal third place finish.
Everything else has been just a going-through the motions routine since then.
Let's see how he plays his cards now.
I'm sure an AG position in an Obama administration sounds good to him.
Unfortunately for the nation, that would be an utter disaster.