“I’m sometimes the only person with a Southern accent in the room,” he said, particularly when he speaks in places such as Myrtle Beach, the nation’s second-fastest-growing metropolitan area in recent years.

Yet South Carolina still teeters on the edge. The share of residents in economic distress is fourth-highest in the nation, according to the Economic Innovation Group, a Washington organization that advocates centrist positions. The state has a lower median household income, higher poverty and a lower share of bachelor’s degrees than the national averages, Census Bureau data show.

Charleston resident Rachel Nelson, 35, said she plans to vote for the first time in the coming weeks. She hasn’t decided for whom, and her only issue is a higher minimum wage and the right to unionize.

“My kids are smart and I have no way to send them to college,” said Nelson, who earns $9 an hour at a fast-food restaurant and is the sole provider for three children. “They haven’t had new shoes since August, and I had to put off paying bills to do it then.”

South Carolina’s economy once was dominated by textile mills that departed in search of cheaper workers, leaving the state moribund and in search of new industry. Then, 20 years ago, BMW located its first U.S. plant between Greenville and Spartanburg. Parts manufacturers and suppliers followed.

What had been a tattered area blossomed into one with a median household income about 9.4 percent above the statewide average. The industry created resilience: While the U.S. battles slow global growth and a strong dollar, South Carolina’s factory payrolls show a stronger rebound than the national recovery.

The “good fortune is largely due to an astonishing run of economic development that helped draw thousands of high-paying manufacturing jobs,” said a report released Tuesday by Mark Vitner, senior economist for Wells Fargo Securities in Charlotte, North Carolina.

Most of the development came from overseas: Recent data from the International Trade Administration show overseas firms employ 115,900 South Carolinians, or 7.6 percent of the state’s private sector workforce, the second-highest share in the U.S., Vitner wrote.

Both Gossett and the state Chamber of Commerce boast that South Carolina is the least unionized workforce in the U.S. The United Auto Workers union covets the plants, and those of other auto manufacturers in Tennessee and Alabama, but has been unable to gain traction. Democratic candidates will face pressure from labor supporters to speak out on the issue, but also will have to consider the prosperity the factories brought.

Pointed Retort