Yadkinville, N.C., is an unlikely launching spot for a senator from Massachusetts.
“You ever seen ‘The Andy Griffith Show?’ ” Mo Cowan once said in an interview. “It was a simple life. Most folks, if they weren’t in the farming industry, worked in factory positions. You knew your neighbors, and most of your neighbors you were related to.”
But Cowan said Wednesday that his upbringing in that largely segregated tobacco town was essential to his rise. It was there that his mother, a widowed seamstress, instilled in him the confidence that helped him navigate a town where he saw the Ku Klux Klan, still active in the 1970s, burn a cross, march on his high school, and hand out literature on Main Street.
Cowan went on to attend Duke University, land a partnership at a powerful Boston law firm, and become a top adviser to Governor Deval Patrick. On Friday, he moves on to the US Senate, the eighth African-American to serve in the chamber.
“My mother told me days like today were possible,” Cowan said after the governor introduced him as the state’s interim senator.
Though unknown in Washington and relatively new to Massachusetts politics, Cowan is a prominent figure in Boston’s legal circles.
After moving to the city 22 years ago to attend Northeastern Law School, Cowan, 43, became a respected mentor to young African-American lawyers and professionals in a city known as a tough place for newcomers and people of color.
He helped Governor Mitt Romney identify black lawyers who would make good judges. He recruited black lawyers for his law firm, Mintz Levin, and for Middlesex District Attorney Gerard T. Leone Jr. And he held social events known as “friendly takeovers,” in which young black professionals gathered at fashionable downtown nightspots.
“When people came to Boston, people would say, you have to meet with Mo Cowan,” said E. Macey Russell, a friend and fellow lawyer. “And it’s not that he could promise anyone jobs. But he was always the person who would have coffee with you, and try to help you navigate being a person of color who wanted to work in a law firm in Boston.”
Damian W. Wilmot, a partner at Goodwin Procter, was one of those people who called Cowan, when Wilmot was an undergraduate in the 1990s.
“He’s someone who always had an open door to folks like me, a young lawyer of color in this city,” Wilmot said. “He was someone who I could go to and talk to and was very much an early mentor to me, and then became a close friend.”
Cowan’s relationship with the governor evolved in much the same way.
Cowan first metPatrick two decades ago, when Cowan “essentially cold-called” Patrick after hearing him speak at a legal event. Patrick, a charismatic lawyer from the South Side of Chicago, clearly saw in Cowan a kindred spirit, and the two “began what has been a longtime and fulfilling and worthwhile relationship for me, personally and professionally,” Cowan said.
Patrick hired Cowan as his chief legal counsel in 2009, after persuading him to give up his lucrative job as a partner at Mintz, the politically connected law firm where Cowan had worked for the previous decade. It was hard to say no to the man who had been a mentor, especially after the governor invited Cowan and his wife, Stacy, for dinner at Patrick’s retreat in the Berkshires. Cowan was elevated to chief of staff in 2010.
Stacy Cowan is also a lawyer, and the couple has two sons, Miles, 8, and Grant, 4.
When William Cowan, who lives in Stoughton, recently left the Patrick administration, he said he was planning to return to the private sector. But that was before the governor asked him to serve as interim senator, a post that will no doubt increase his job prospects after he finishes his brief tenure.
Back in Yadkinville, a town of 2,200 about 25 miles west of Winston-Salem, word was spreading fast Wednesday that Cowan had been named a US senator, years after he was the first from his high school to attend Duke.
“I figured he would be a doctor,’’ said Sherry Long, a cousin. “He was always so brilliant.”
Long recalled Cowan’s taking the SAT “just for fun” when he was in the seventh grade and she was in high school studying for the test.
“He was continuously in front of some educational channel or had his nose in a book,” she said.
Tony Craver, a friend from elementary school, said he was filled with pride for Cowan and his town.
“Good old Yadkin County can succeed all the way up in Massachusetts,” Craver said. “That’s awesome.”Michael Levenson can be reached at mlevenson@
globe.com. Follow him on Twitter @mlevenson