Vice President Biden kicked off the Obama administration's post-Republican convention today, going after Mitt Romney's opposition to the auto bailout in the key state of Ohio.

Romney "said if we stepped in to help, GM would be 'the living dead,' " Biden told a crowd in Lordstown, Ohio, where General Motors is investing another $200 million in a local plant.

Biden also contrasted Romney's opposition to the auto bailout with his efforts to secure federal help for his consulting company when it struggled.

"The way they reorganized cost the government $10 million," Biden said. "Imagine that -- it was one thing when a million middle-class jobs were on the line. It was another when his own financial interests were on the line."

Biden spoke the night after Romney formally accepted the Republican presidential election, and four days before the Democrats open their own convention in Charlotte.

Bain & Co. -- the parent company of Bain Capital, the private-equity firm where Romney made his name -- took new taxpayers' dollars during a loan restructuring during the 1980s.

"Vice President Biden demonstrated once again today that this administration doesn't know how our economy works," said Romney spokeswoman Michele Davis. "Making false accusations can't distract Americans from their failed record on the economy and jobs."

In Ohio -- a potentially decisive state -- Biden also criticized Romney's running mate, Rep. Paul Ryan, R-Wis. In his acceptance speech, Ryan appeared to blame President Obama for the closing of a GM plant in his hometown of Janesville, Wis.

"Congressman Ryan was right about one thing," Biden said. "It was devastating for the community and those people -- but what he didn't tell you was that plant in Janesville actually closed while President Bush was still in office."

Biden added: "And what they didn't say is, but for the sacrifices you made, and the courage of the president, all those GM plants would have closed."

Romney aides said that, even with gains in the car business, jobs have been lost and the economy has continued to stagnate under President Obama's policies.

"The vice president can't answer for this administration's unfulfilled promises and failed record," said Brendan Buck, a spokesman for Ryan. "The president inherited a troubled economy, but he's not made it better -- he's made it worse, with fewer jobs and lower incomes for middle-class families."

Buck added: "Like many towns across America, Janesville, Wisconsin, is still waiting for the recovery the president promised."