An outspoken social conservative, Santorum at times seemed to let his opposition to single-parent families and children born out of wedlock overshadow his economic pitch. At a weekend campaign stop in Lima, Ohio, he said lack of attention to family dysfunction and other social issues was "damning" people.
But Santorum's consistent, values-laden message again helped him outperform Mitt Romney in key segments of the Republican electorate.
In Ohio, born-again or evangelical Christians give Santorum a double-digit lead, according to exit polls taken for The Associated Press and the television networks. Likewise, those who say it matters a great deal that a candidate shares their religious views gave Santorum a lead of about 30 points.
Gingrich's sole victory in Georgia breathed some new life into a candidacy that has gone winless since South Carolina weeks ago.
He had originally planned to campaign extensively in Ohio as well as Tennessee, but dialed back when it became clear a win in Georgia was the best and most realistic outcome he could hope for. The win offered some plausibility to his all-Southern strategy, which will be tested anew in primaries in Alabama and Mississippi next week.
Associated Press writers Kasie Hunt in Boston, Tom Beaumont in Atlanta and Steve Peoples in Steubenville, Ohio, contributed to this report.
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