Doug, a former director of the Congressional Budget Office and top economic policy adviser to President George W. Bush and the 2008 McCain for President campaign, wants to fix revenues as a share of Gross Domestic Product.

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Still, Romer will be the second major administration figure and economic adviser to leave office recently, following the exit of former budget director Peter Orszag last month.

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He served as director of the Congressional Budget Office from 2003 to 2005, and as chief economic policy adviser to John McCain in 2008.

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