Jay Rockefeller , a former West Virginia governor and longtime U.S. senator who stood as the sole Democrat and final figure of his prominent family's political line, has died at the age of 89.

His passing occurred Thursday night at his residence in Washington, according to Mary Stewart, vice president for external affairs at public broadcasting station WETA, where Rockefeller’s wife, Sharon, serves as president and CEO.

Hailing from one of America's wealthiest dynasties, Rockefeller devoted 50 years to public service in one of its poorest states. His career began in 1964 as a worker for an anti-poverty program, leading to two terms as governor starting a dozen years later, followed by three decades in the U.S. senator role.

"I could not imagine a more rewarding career," Rockefeller said upon his retirement in 2015.

Born John D. Rockefeller IV in New York City, he was the great-grandson of Standard Oil Co. founder John Rockefeller, who died a month prior to his birth. His father, John D.…