Panic seized many Democrats last week, as polls showed that the choice of Sarah Palin as running mate had not only energized Republicans but given John McCain a solid boost among independent voters.

Why the panic? After all, the latest poll trend could easily be dismissed as merely the typical post-convention “bounce” for the GOP. On Aug. 28, the final day of the Democratic convention in Denver, the Gallup daily tracking poll reported Barack Obama ahead by a whopping 8 points without generating any panic by Republicans. Why should Democrats freak out over a McCain bounce that peaked at 5 points Sept. 8-9?

Yet there they were, top Democratic sources — some named, some anonymous — confessing to reporters previously unspoken doubts about the strategic soundness of the Obama campaign.

“There is a growing sense of doom among Democrats I have spoken to,” one Democratic fundraiser told Andrew Ward of the Financial Times. “People are going crazy, telling the campaign ‘you’ve got to do something.'”

Former Clinton administration chief of staff Leon Panetta told the New York Observer the Obama campaign was “totally reactive now” and seemed “intimidated by the Palin pick.”

“The campaign has been knocked off stride,” a Democratic operative told the Los Angeles Times, while the shifting poll numbers caused Obama backer Rep. Elijah Cummings of Maryland to say, “Whenever you see that kind of movement, you ought to be concerned; you ought to try to address it.”

WHEN OBAMA started slamming Palin, however, two anonymous Democratic strategists told Nedra Pickler of the Associated Press that this task should be assigned to Obama’s running mate, Sen. Joe Biden. But Biden, meanwhile, was busy telling a New Hampshire audience that “quite frankly [Hillary Clinton] might have been a better pick than me.”

Granted, a 13-point poll swing in the space of 11 days would rattle any campaign, but the panic induced among Democrats was in part due to the extraordinary expectations raised by the Obama campaign, and the surprise of McCain’s choice of Palin.

Democrats had been encouraged to believe that Obama would prove so overwhelmingly popular that he could compete even in deep-red Republican states.

Three months ago, Obama strategist David Plouffe wowed the Washington press corps with a presentation naming as “battlegrounds” such states as Georgia, North Carolina and Montana — even Alaska! — that President Bush had carried by double-digit margins.

These prospects were only imaginable in the event of a massive Democratic landslide, which Team Obama strongly urged Democrats to imagine. Yet the latest polls indicate nothing of the kind — McCain leads by double-digit margins in Montana (+11), Georgia (+13) and North Carolina (+17). Polls also show McCain holding steady leads in such swing states as Missouri and Florida, while holding close in Democatic blue states like Pennsylvania and Michigan. (And, for obvious reasons, Alaska is off the table.)

Instead of the landslide that Plouffe seemed to promise, what Democrats now face is another hard-fought battle for a relative handful of swing states, and recent experience doesn’t give them confidence that they can win that kind of fight — especially with Ohio now trending Republican.

THIS EROSION of Democratic confidence was clearly accelerated by McCain’s choice of Palin as his running mate. It pushed Democrats into panic mode for several reasons, including their consciousness of hurt feelings within their own ranks over Obama’s snubbing Hillary Clinton as his running mate. (Hillary seems less than eager to help Obama push back against the Palin phenomenon.)

Perhaps the most obvious cause of the Palin-induced panic was that Team Obama was so clearly caught by surprise. Obama’s website had featured a page called “The Next Cheney,” highlighting opposition research on nine potential GOP running mates — and the Alaska governor didn’t even make the list. (The page has since been updated to feature anti-Palin material.) In fact, the New York Times reported, the Obama campaign had been preparing ads to run against Mitt Romney, but had no response ready for the Palin pick.

Their failure to anticipate McCain’s choice of Palin undermined Team Obama’s carefully cultivated reputation for strategic genius. And the subsequent poll surge undermined another source of Democratic confidence: A belief that the unpopularity of Republicans would provide an automatic advantage to whoever won the Democratic nomination.

Nate Silver, the statistics buff and Obama supporter whose poll analyses and projections have made him a media favorite, looked at the post-Palin polls and mused that “perhaps the partisan composition of the electorate had never shifted as much from 2004 as it has appeared to.”

If that shift was never as large as earlier polls suggested, and if the Palin effect continues to energize Republicans and win over independents, then the Democratic panic may have only just begun.

Robert Stacy McCain is co-author (with Lynn Vincent) of Donkey Cons: Sex, Crime, and Corruption in the Democratic Party. He blogs at The Other McCain.