Vice President Joe Biden keeps up criticism of Mitt Romney's business past

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KEENE, N.H. — The presidential campaign debate over Republican Mitt Romney's tenure at a private equity firm is going down the drain.

Vice President Joe Biden argued Tuesday that Romney's experience doesn't make him anymore qualified to be president than it does to make him a plumber.

Romney argues that his business experience makes him best suited to fix the economy and create jobs.

Biden, on his fourth campaign visit to New Hampshire this year, also argued that Romney would take the nation back to the 1950s on social policy, to the Cold War on foreign policy and to Bush administration policies on the economy.

Most of Biden's speech in Keene, N.H., echoed Obama campaign talking points — that Romney's success making money for investors isn't reason alone to be elected president.