Sarah Palin skipped over the low expectations set for her debate with Joe Biden in St Louis, brazening her way through with a firm grip on her talking points, a few winks, and a pitch so folksy - "doggone it", "you betcha" - that even George W Bush, the aw-shucks standard-setter, would have sounded like Henry James beside her.
But the redemption of John McCain's running mate from Alaska was undercut by news that same day from another northern state with hunters and hockey moms: the McCain campaign was pulling out of Michigan, the second-largest of the states carried by the Democrats in 2004 that McCain had been hoping to pick off. For him to decide, with a month to go, that his money was better spent in states that were threatening to defect to Barack Obama, such as Florida and Virginia, represented a distinct tactical shift.
The move's real jolt, though, lay in its broader implication. All campaign, Obama had laboured under the shadow of the great but tottering American Rust Belt. For all his talk of expanding the electoral map into the South and West, many Democrats worried he would leave a gaping hole in the middle, in Pennsylvania and Michigan, crucial elements of the party's coalition, and Ohio, which it so coveted. Hillary Clinton had handily won the primaries in Pennsylvania and Ohio, prompting speculation that the post-industrial swath between Allentown and Toledo was resistant to the silken, half-Kenyan senator.
Particularly troubling was Michigan, where "Reagan Democrats" had first entered the political taxonomy, in the working-class suburb of Macomb County. Obama had not campaigned in the state's primary because its timing had violated party rules, and he had throughout the race held up as proof of his willingness to tell hard truths a speech he gave to car workers in Detroit demanding that they increase fuel efficiency, a sore subject in a state whose Ford and Chevy plants have been badly hurt by the Prius and its ilk. Many in Michigan hold the state's Democratic governor partly to blame for its plight - unemployment is the highest in the country. And a sex scandal involving the young black former mayor of Detroit has not helped race relations in a state that has experienced worse than usual white flight - Detroit's population is more than 80 per cent African American.
Sure enough, throughout the summer, Obama struggled to pull ahead in the three big states, even as he showed surprising strength in more white-collar Republican strongholds such as Virginia and Colorado. An awful irony loomed for Democrats - how was it that, in a year when the poor economy had put them in such prime position, Obama might lose the very states that had fared worst under Bush?
For all Obama's "new politics", part of the rescue job would fall to older politics: labour muscle. Despite dwindling ranks, organised labour has enhanced its turnout operation to the point where union members now make up a disproportionate share of the Rust Belt vote - and vote Democratic far more than their non-union compatriots. But this year's assignment required a sales job all its own, and the union leaders have approached it with all the subtlety of a pipe-fitter's blowtorch - Obama is best for workers, members are told, and if they have a problem with that, they should get over it. I observed this in Reading, Pennsylvania, where the Teamsters president, James P Hoffa, son of the late, legendary leader of the same union, told workers at a truck depot, grocery warehouse and sweets factory that "Barack O-bomber", as he pronounced it, was the one.
The most candid variation came in a recent speech by an AFL-CIO official, Richard Trumka, in which he recounted his response to an old acquaintance in his home town who said she wouldn't vote for Obama because he was black. "Nemacolin is a dying town," he told her. "There's no jobs here. Our kids are moving away because there's no future here. And here's a man, Barack Obama, who's gonna fight for people like us. And you wanna tell me that you won't vote for him because of the colour of his skin? Are you out of your ever-lovin' mind, lady?"
Perhaps the financial crisis, which has been followed by truly dismal car sales figures, has provided a clearer verdict than the region's slower overall decline, which workers knew had far more fathers than just Bush. No matter what, the import was clear. If Michigan was turning Democrat, so must be key pockets of Ohio and Pennsylvania. It still wasn't going to be easy, but Obama's torturous, year-long courting of the Rust Belt - all those bowling alleys and factory floors - might finally be making an impression.
Hoping to prevent this, McCain has launched an attack, seeking to renew questions about Obama's association with a 1960s radical-turned-Chicago education professor. As Palin put it, he would pal around with terrorists.
But then came another day in the markets. And Joe Six-Pack might have been too scared watching Monday's 800-point plunge to worry about terrorists - even 63-year-old white ones on the college faculty.
Alec MacGillis is a staff writer for the Washington Post