"I hope that each of you and the state that I love can understand that this is an entirely personal decision," Rockefeller said at the news conference. “It is not a political decision.”
But who will replace him? That’s where things get tricky.
Representative Capito, the daughter of a former three-term West Virginia governor and the first-ever woman elected to the House from the state, finally acceded to requests from GOP leaders to run for statewide office in late November of last year.
But the GOP’s assertive conservative wing sees some parts of her background – her broadly moderate positions embodied by her membership in the Republican Main Street Partnership, a middle-of-the-road GOP organization; her pro-choice stance; her vote to raise the nation’s debt ceiling last year – as reasons to worry.
"Now that Rockefeller has taken himself out of the race, the door is wide open for Republicans in West Virginia to nominate a true conservative," said Matt Hoskins, the executive director of the Senate Conservatives Fund, a group founded by former Sen. Jim DeMint of South Carolina, a tea party firebrand. "President Obama lost the state by 26 points, so there's no reason a courageous conservative can't win this race."