LAS VEGAS - Vice President Joe Biden is denouncing Republican Mitt Romney as a candidate with something to hide.
In an address to the National Council of La Raza in Las Vegas, Biden compared Romney unfavorably with his father, George Romney, who released 12 years of tax returns during his unsuccessful White House bid in 1968.
Mitt Romney has released his 2010 return and an estimate for 2011.
Biden, to applause from the Hispanic conference, said that Romney - quote - "wants you to show your papers, but he won't show us his!"
The remarks underscored the Obama campaign's latest effort to portray Romney as secretive, and highlight Romney's past hardline immigration stance.
A Romney campaign adviser accused the Obama campaign of "desperation" with an attack aimed at diverting attention from unemployment and jobs.
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