Santorum picks up South Carolina support

Washington (CNN) - Former South Carolina Rep. Gresham Barrett will endorse Rick Santorum for president this weekend, CNN has learned.

Barrett, who served four terms in the House and ran unsuccessfully for governor in 2010, will serve as Santorum's campaign chairman in the key early primary state as well as his "National Energy Policy Chairman."

Santorum, a former Pennsylvania senator, endorsed Barrett during a heated four-way Republican gubernatorial primary fight in 2010.

Barrett narrowly made it to a runoff against South Carolina Gov. Nikki Haley, but Haley cruised to the nomination two weeks later.

The Republican presidential candidate will make the announcement during a multi-stop tour of Columbia on Saturday. Santorum will also roll out his state finance chairman, finance consultant and several "coalitions leaders," according to his campaign.

Barrett hails from the heavily evangelical South Carolina upstate, a region Santorum is working hard as he campaigns for the nomination.