Columbia, S.C. — As Newt Gingrich toured the Palmetto State this week, holding four town-hall meetings, national headlines focused on his stray comments about Mitt Romney. But on the ground, it was Gingrich’s well-informed takes on state issues, from labor policy to immigration, that drew interest — and stirred applause at Tommy’s Ham House in Greenville and at the Sottile Theatre in Charleston.

“All politics is local,” of course, is a familiar axiom. Every politician caters to the hometown crowd. But as the winter primaries near, Mitt Romney should take note: Gingrich’s eagerness to discuss state concerns, and make data-driven arguments, is bolstering the former speaker. He may not have Romney’s organizational strength, but when it comes to wooing undecided voters, Gingrich’s knowledge is power.

At recent events, Gingrich has spoken extemporaneously, often for an hour, taking questions from attendees and bantering with locals. In South Carolina, he won rave reviews for this approach. All of the head nods, however, were more than a response to Gingrich’s well-organized presentations. Watching the crowds, one saw that Gingrich’s substance on regional issues was crucial to his success.

During stops in Charleston and Bluffton, for example, Gingrich’s command on seaport policy, an arcane topic within the Beltway, was largely ignored by campaign reporters. But South Carolina Republicans noticed. They cheered when Gingrich pledged to help “modernize” the state’s ports, which, residents say, need to be deepened in order to sustain the state’s competitiveness, not only globally but also with neighboring Georgia, which has decided to dredge the Savannah River.

How he made this point was striking. A former college professor, Gingrich used his understanding to detail his own solutions and simultaneously showcase his grasp of the changing shipping economy. He addressed the port’s key commercial challenge — accommodating supertankers, which will be arriving to Charleston in droves after the Panama Canal expands — with ease and, more notably, statistics.

Standing up on stage, his arms outstretched, Gingrich empathized with South Carolina’s economic situation, and went beyond conventional talking points, blending his energy platform with city politics and growing complaints about federal inaction. To an outsider’s ear, Gingrich’s state-related rhetoric could be incomprehensible, full of terms rarely heard on cable news. Yet it clicked with those he was looking to reach.

“There’s 29 billion dollars’ worth of natural gas offshore,” Gingrich said in Charleston, offering drilling as a potential revenue boost for the ports. He explained, “I’d like to see it developed, with 50 percent of the resources going to the federal government, 37.5 percent going to the state government here, and 12.5 percent going to infrastructure and to the development of land conservation,” including ample funds for port renovation.

Sources close to Gingrich tell me that this über-local, studied routine is not a recent project but an important campaign strategy. When many of Gingrich’s senior political advisers resigned in July, the candidate was forced to rethink his candidacy. Battling the Washington press corps during debates, a widely discussed Gingrich maneuver, became one of his chief focuses. The second focus, less mentioned, was his commitment to run a “positive, solutions-oriented campaign,” and he told his team to keep prepping him on myriad issues, local and national, in case he surged.

Now, after months of quietly rebuilding his political team, Gingrich reenters the limelight ready to tangle with Romney, to be sure, but also ready to assert himself as the “non-establishment” contender, as the Republican who can connect with Main Street voters in small towns. For Gingrich, a multimillionaire consultant, to make this convincing, he needs to sound convincing. So far, campaign sources believe he is succeeding. They’re pleased with the South Carolina swing. While Romney is producing videos about President Obama, and doing few retail events, Gingrich is wowing them on seaports.