A Republican with knowledge of the situation told The Associated Press that Romney has chosen Ryan. The Republican spoke on condition of anonymity because this person was not authorized to disclose the decision.
Romney was expected to introduce Ryan during a rally Saturday morning in Norfolk, Va.
This is not the first time Ryan has sparred with the Obama administration in a prominent way. At the president's health care summit in 2010, the House Budget Committee chairman delivered a broadside against President Obama himself:
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