Here is how various news organizations preview tonight's third and final debate between McCain and Obama:

New York Times:

But this promises to be his last chance for direct confrontation. Watch to see how he uses it and whether he spends more time trying to restore voters' confidence in himself or to raise doubts about Mr. Obama's readiness to serve as commander in chief. The tone he strives for and the degree to which he hammers Mr. Obama will say a lot about where he thinks the race stands now and how he will conduct the rest of the campaign.

Washington Post:

The expectations for the debate have been set at impossibly high levels. What got McCain the Republican nomination was not his dominance on stage in the debates, although he had several very good nights. It was that Republican voters found his opponents, one by one, to be wanting. So far the debates have not left voters with that same impression of Obama. He has worn well in these important tests.

Politico:

The challenge confronting McCain is an opponent who rarely gets thrown off his game. Once considered a potential liability, Obama's calm and cool nature is emerging as his overriding virtue and strategy in a campaign transformed by a financial crisis -- and it's a trait well-suited for debates that allow little of the give-and-take that might fluster the Democrat.

By all accounts, the even-keeled temperament reflects the real Obama. But it is also part of a fiercely protected public image that he is selling to voters, meaning the odds that McCain scores points from either forced or unforced errors may be low.

The Atlantic:

In an election season where excitement for the unknown has replaced fear of the unknown, John McCain has a decision to make. Either he can try to reverse the collective valence of the nation -- that is, scare the pants off of everybody, or he can try to replace the object of the excitement. Decisions about Obama's character -- who the guy is -- have hardened, and not in a good way for McCain. McCain et. al. asked "Who Is This Guy?" Debate viewers saw a charming, calming nerd, not a dangerous, unknown, fussy Chicago pol. Or whatever. You can't force people to believe something that doesn't seem to be there.