From ABC News:

“Make no mistake about this,” Biden responded. “Hillary Clinton is as qualified or more qualified than I am to be vice president of the United States of America. Let’s get that straight. She’s a truly close personal friend, she is qualified to be president of the United States of America, she’s easily qualified to be vice president of the United States of America, and quite frankly, it might have been a better pick than me. But she’s first rate, I mean that sincerely, she’s first rate, so let’s get that straight.”

Spokesman Ben Porritt offered this response from the McCain camp: “Barack Obama’s most important decision of this election, and Biden — the candidate he selects — suggests, himself, that he wasn’t the right man for the job, and that Hillary Clinton would have been a better choice. Biden certainly has a credible viewpoint on this.”