Vice President Joe Biden attacked Mitt Romney’s record for outsourcing when he was governor of Massachusetts and while he was in private business. Biden was speaking to engineering plant workers in the country’s heartland of Davenport, Iowa. Biden said the policies of President Obama have helped to revive manufacturing in America and spurred ancillary expansion in communities that surround the production hubs.

Biden said, “The only way for out middle class to grow is to build an economy capable of supporting that same middle class.” He added, “Manufacturing is not the only element, but is critical to bringing back our middle class.”

In the last ten years, over 5.8 million jobs in the manufacturing industry have been lost. However, Biden said that since 2010 over 400,000 of those have returned through insourcing.

Biden said that when Romney headed venture capital firm Bain Capital, companies that it owned outsourced business overseas. While governor of Massachusetts Biden said Romney, on repeated occasions, slashed funding in training the workforce. Romney, Biden said, also vetoed specific legislation designed to stop Massachusetts from outsourcing contracts for the state.

The vice-president said that Massachusetts lost manufacturing jobs twice as fast as other parts of the country during Romney’s administration. Biden also said that Romney’s policies and business practices benefited both the wealthy and most powerful, often causing the middle and working class to suffer because of it.

Biden is giving framing speeches that will outline the administration’s ticket for the general election.