He announces he's suspending his campaign and skipping Friday's debate, invites Obama to return to Washington with him to work on the economic crisis.

Amazing! A few insta-reactions:

--Having thrown a Hail Mary with the Sarah Palin pick and feeling he scored a touchdown (although that's certainly debatable), he may have concluded that risk-taking works for him. He's always known the fundamentals of the race were against him and would require some out-of-the-box thinking.

--He was losing control of the campaign narrative. The Palin surge/convention bounce is nearly kaput. Obama seems to be tied or ahead in Virginia and Florida is back in play. Today's WashPost poll showed McCain nine points down and distrusted on the economy. The media's interest this week is in Rick Davis's lobbying and Sarah Palin's comical photo-ops. Things could hardly get much worse.

--Steve Schmidt's philosophy seems to be that it's always better to be on the offensive, and this certainly counts as that. As Ben Smith puts it, Obama's choice--come to DC on McCain's terms or dismiss this as a stunt?--"is not an easy or obvious one."

--Minor fringe benefit: The foreign policy debate was supposed to be the friendliest turf for McCain, but the financial crisis promised to creep into the debate constantly and crowd out the focus on world affairs. If McCain can reschedule it for later in the campaign--although those negotiations are not likely to be cordial!--he might get a cleaner shot at Obama on those issues.   

--Major downside: The media will treat this as a sign that McCain is desperate and knows he's losing. But the public may see it differently. If he gets credit for showing leadership on the economy, that will undermine Obama's greatest advantage.

--Ultimately: The outcome should largely hinge on the substance of what McCain says and does. He may get some instant credit for "leadership"--but will still need to play a convincingly important and useful role in the Washington legislative process, one that pleases independents and his base alike. Far easier said than done in that snake pit. 

--Michael Crowley