By Catalina Camia, USA TODAY

Democratic Sen. Jay Rockefeller will announce Friday that he will not seek a sixth term in 2014, setting the stage for a pitched battle for his Senate seat in West Virginia.

He is slated to announce his plans in Charleston.

Rockefeller, a former two-term governor and current chairman of the Senate Commerce Committee, has been in the Senate since 1985. He has sparred in recent years with the state's coal mining industry and is a staunch supporter of President Obama, who is unpopular in the state.

Rockefeller told the Associated Press he wants to spend more time with his family. "I've gotten way out of whack in terms of the time I should spend with my wife and my children and my grandchildren," he said.

Rockefeller is the first Democrat up for re-election in 2014 to announce his political plans, which will give the party plenty of time to recruit a candidate. Rep. Shelley Moore Capito, a Republican whose father was once governor, has declared her intention to run for the Senate in 2014.

Democrats currently have a 55-45 voting edge in the Senate and have 20 seats to defend in the next election cycle.

Rockefeller came to West Virginia to work on anti-poverty programs and stayed in the state to build a political career. In 1972, Rockefeller lost his first bid for governor -- to Arch Moore, Capito's father -- before going on to serve two terms from 1977 to 1985.

As a senator, Rockefeller is known for his work on health care legislation, among other issues. He was a champion of the "public option," a government-run health insurance program, which did not make it into the final version of Obama's health care law.