West Virginia ? Gov. Joe Manchin, a centrist and popular Democrat known for his calm, compassionate handling of a coal mine disaster that killed 29 in April, declared Tuesday that he will run for the late Robert C. Byrd’s U.S. Senate seat.

The bid marks the latest rise in profile for the 62-year-old Manchin since the former state lawmaker captured the governor’s office in 2004 after a term as secretary of state. He became chairman of the National Governors Association earlier this month, enjoys high approval ratings in his state and was seen as a comforter-in-chief to victims’ families following April’s Upper Big Branch mine explosion and the 2006 Sago mine disaster.

Byrd was 92 when he died June 28 as history’s longest-serving member of Congress. He was renowned for his mastery of the Constitution and complex Senate procedures, and for securing funds for his home state. Manchin said no one could truly replace him.

“If I am so fortunate and honored to have the support of the people of West Virginia, I can’t fill his shoes,” Manchin said. “I only hope I would be able to follow in his footsteps and continue to help people of West Virginia.”