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A Mitt Romney staffer pokes his head out of the campaign's office in Arlington, Va., on July 13, threatening to call the police as a group of demonstrators organized by MoveOn.org block the entrance. The protesters' Caribbean-themed clothing is meant to critique Romney's opaque financial holdings in Bermuda and the Cayman Islands. Groups across the country have delivered letters to the GOP candidate's offices demanding that Romney release more than just the two years worth of tax returns he has made public.