Senator Joe Biden accepted the Democratic vice-presidential nomination on Wednesday night with an ode to his middle-class upbringing and a blistering attack on John McCain.

On tax policy and the war in Iraq, on healthcare and terrorism, on the minimum wage and on Russia, Biden said, the contrast was clear between McCain and the Democratic presidential nominee, Barack Obama.

“Again and again,” he said, “on the most important national security issues of our time, John McCain was wrong, and Barack Obama was proven right.”

He said McCain has supported Bush’s policies that Biden says have driven the US economy into a ditch and backed him on a war that is costing American taxpayers $12 billion a month. “These times require more than a good soldier; they require a wise leader, a leader who can deliver the change everybody knows we need.”

Part of Biden’s assignment on Wednesday night was to connect with struggling American families and to portray himself and Obama as products of the middle class who would fight to restore the American dream.

Biden, who referred to his childhood struggle with stuttering, made a few verbal slips, including referring to McCain as “George”. “Freudian slip, folks,” he said. “Freudian slip."