As Obama sinks in the polls, Dennis Keohane wonders if it’s possible that democrats might still change their mind about nominating him.

Will Hillary outsmart Obama and take the nomination at the last minute?

Many of us familiar with Hillary Clinton’s approach to achieving her goals refused to believe that she ever gave up all hope of winning the nomination and the presidency. Her words and actions on the subject of the convention itself always left the door open for a return, should Obama falter or suffer some calamity.

Her artful evasions were enough to lull journalists and (more importantly) Obama and his supporters into the presumption of inevitability. No further rumblings of a mass protest in Denver should the first black candidate be denied his rightful due were heard. After all, he received enough publicly expressed support from super delegates to put him over the top. And he won the popular vote in the primaries, we were assured, lending legitimacy to the super delegates who voiced their support.

Everyone presumed the presumptive nominee was a lock.

Now there are a few signs that Hillary may be making her move. …

ABC news reported yesterday that Hillary Clinton does not rule out putting her name in nomination, contradicting earlier press reports.

Many people, including no doubt a goodly number of nervous Democrat super delegates, are asking themselves the David Brooks’ question about Obama’s standing in the polls: “Where’s the landslide?” After evaluating him for several months, voters in the middle still aren’t ready to embrace him.

National polls show not only a tightening of the Obama-McCain race to a statistical dead heat but momentum toward a McCain lead, something inconceivable only weeks ago. The specter of an Obama collapse has to haunt more than a few super delegates.

Buyer’s remorse seemed evident and growing among many Democrats toward the end of their primary season when Obama lost again and again to Clinton, even as the delegate math was by then stacked in his favor. That remorse was put on hold (but apparently not resolved) by Obama’s seeming to secure the nomination and the subsequent popular boost he enjoyed at first. But lately the candidate with a difference has had a hard time living up to his promise to be a new kind of politician.

According to RealClearPolitics, Obama has 1766.5 pledged delegates, 352 short of the 2118 needed to secure the nomination. He also has 463 super delegates, which puts him over the top — if they hold. If a combination of Clinton campaigning and nervousness can cause a hundred and twenty or so super delegates to sit out the first ballot, Obama does not get the nomination on the first ballot and perhaps not at all. After that first vote a great many pledged delegates and all the super delegates are free to vote as they choose.

He has a good point.

If you keep an eye on Larry Johnson’s No Quarter, you can see that there are plenty of irredentist Hillary supporters out there in the ranks of the democratic left.