Former Virginia Govs. Tim Kaine (left) and George Allen after a Senate debate in Richmond, Va., on Dec.. 7, 2011. Steve Helber/AP hide caption

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An image from the Republican National Committee's Facebook page advertises its new "Social Victory Center" app. RNC via hide caption

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That New Friend You Made On Facebook? He Might Be Named Mitt Or Barack
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Fairchild's first microchip combined four transistors, six resistors and their interconnecting wires onto a single sliver of silicon, in 1960. Today's microprocessors can employ more than 1 billion transistors. Fairchild/Courtesy of the Computer History Museum hide caption

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