Rick Santorum, a Pennsylvania Republican, served in the U.S. Senate from 1995 to 2007. Prior to that, he was elected to two terms in the U.S. House.
Known as a strong social conservative, Santorum finished the 2012 GOP Presidential Primary as runner-up to Mitt Romney.
Santorum announced his bid for the 2016 Republican presidential nomination on May 27th, 2015.
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