An extraordinary political drama is unfolding in Alaska as both the FBI and federal grand juries investigate Ted Stevens, the nation’s longest-sitting Republican senator, and his son Ben Stevens, a former state Senate president whose office was twice searched by federal agents last year.

The wide-ranging public-corruption investigation started with bribery allegations in the Juneau statehouse. It now threatens one of the most powerful Republican politicians in Washington, D.C., and could reshape politics in the state.

Already Bill Allen, the former chief executive of the oil-services contractor VECO, has pleaded guilty to bribing state lawmakers in exchange for votes favoring the oil industry. Allen, a friend and political backer of Ted Stevens, has pledged to cooperate with federal officials. And it was Allen’s involvement in the remodeling of Stevens’ home in Alaska that led to the FBI’s raid last week.

“Our state needs to grow up and clean up,” Alaska’s GOP governor, Sarah Palin, said last week. “We need to prove to the rest of the nation that our government is as clean as our environment and … that we can do it right.” Palin says the “culture of corruption” has to end.

About time really.