Trying to extend the buzz of his convention, Obama went back on the trail with Vice President Joe Biden and their wives as well. One of the longest days of his campaign would take him from North Carolina to New Hampshire to Iowa and ultimately Florida, where he begins a bus tour on Saturday.
The monthly jobs snapshot came out even before organizers in Charlotte had finished clearing away the convention.
"If last night was the party," Romney said in a statement, "this morning is the hangover."
Romney's campaign also unveiled a battery of TV ads in Colorado, Florida, Iowa, Nevada, New Hampshire, North Carolina, Ohio and Virginia. The themes of the ads are tailored to the economic concerns within those states, from growing debt to potential defense cuts to collapsing home values.
The gloomy reaction to job growth came in part because it fell even below the expectations that economists had for August. On top of that, hourly pay fell, the job totals for July and June were reduced, and the number of people in the work force dropped to its lowest level in 31 years.
"This is not even close to what a recovery looks like," Republican vice presidential nominee Paul Ryan told CNBC.
Obama aides said they came out of their convention with momentum and small but consistent leads in the decisive states. With each passing week of little movement in the polls, the campaign attention is turning to what's left: voter mobilization drives and October's three presidential debates.
Associated Press writers Jim Kuhnhenn in Portsmouth, N.H., Thomas Beaumont in Orange City, Iowa, and Nancy Benac and Christopher S. Rugaber in Washington contributed to this report.
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