President Barack Obama lodged an unfair-trade complaint against China - and immediately used it as a wedge against Republican challenger Mitt Romney, whose beleaguered campaign hit another pothole even as it tried to regroup from a shaky few weeks.
Mr Obama told voters in Ohio, where the car industry is important, of his administration's new push for the World Trade Organisation to sanction China for subsidising exports of vehicles and car parts - and costing American jobs.
Mr Romney responded to Mr Obama's actions quickly and dismissively.
Mr Obama "may think that announcing new trade cases less than two months from election day will distract from his record, but the American businesses and workers struggling on an uneven playing field know better", the Republican said.
It was Mr Romney's own campaign, however, that preoccupied many Republican activists.
Just as aides were trying to calm unhappy supporters, a video surfaced showing Mr Romney telling wealthy donors that almost half of all Americans "believe they are victims" entitled to extensive government support.
"I'll never convince them they should take personal responsibility and care for their lives," he tells the donors.
In the video reported by Mother Jones magazine, Mr Romney was referring to the 46% of Americans who do not owe federal income taxes; he put the figure at 47% in his videotaped remarks.
Many of those Americans pay other forms of taxes. While many such households are poor, some families making 100,000 US dollars a year or more pay no federal income tax because of various deductions and credits.
At a hastily called news conference late in the day, Mr Romney conceded the comments were not "elegantly stated" and that they were spoken "off the cuff".