President Barack Obama speaks in the East Room of the White House in Washington, Monday, July 9, 2012. Facing sagging jobs numbers, President Barack Obama seeks to recast the election as a debate over tax fairness, calling for a temporary tax cut extension but just for low and middle income earners. The president�s pitch is aimed at painting Mitt Romney as a protector of the rich while ramping up questions about the Republican challenger�s own wealth. (AP Photo/Susan Walsh)

WASHINGTON (AP) - The Obama election campaign has a politically loaded question it wants the nation's voters to think about: What is Mitt Romney hiding?

It's part of an intensifying effort to cast Romney as a secretive rich guy who keeps his money in offshore accounts and refuses to release more of his tax returns.

Vice President Joe Biden launched a blistering attack Tuesday He said Romney was "making a lie of the old adage, like father, like son" by not meeting the standards his father, George Romney, set when he released 12 years of tax returns during his 1968 presidential bid.

Romney says there is nothing illegal in his private financial records. And his campaign says the Obama is team is just using the attacks to divert from the lackluster economy.

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