But … he’s only in his mid-80s and has served just 21 years. In an age of wizened congressmen who have to be dragged screaming into retirement, surely this youngster has another two or three terms in him.

Charlie Cook rated this seat “solid Democratic” just two weeks ago. That’ll change.

Akaka, 86, has served in the Senate since 1990. He previously served 14 years in the U.S. House of Representatives.

“After months of thinking about my political future, I am announcing today that I have decided not to run for re-election in 2012,” Akaka said in a statement. “As many of you can imagine, it was a very difficult decision for me. However, I feel that the end of this Congress is the right time for me to step aside. It has been a great honor and privilege to serve the people of Hawaii. In 2006, the people of Hawaii gave me an opportunity to continue my service in the United States Senate and I fully intend to serve the last two years of my term in office.”…

The senator, who is of Native Hawaiian and Chinese ancestry, is considered the most beloved Hawaii politician. He is well-regarded in both Washington and in the islands for his gracious manner and spirit of aloha.

But questions have been raised about his effectiveness and whether he should pursue another six-year term.

I figure this increases the GOP’s chances of stealing the seat from zero to, oh, let’s say 10 percent. Yes, there’s a prominent, tested Republican who’s interested in running: Linda Lingle, whose second term as governor just ended, has been hinting at it for months and should be ready to roll now that she doesn’t have to face Akaka. Big problems lie ahead, though. First, Hawaii’s a deep blue state so Democrats predictably have a deep blue bench. Second, although Lingle did win two terms, she didn’t go out on a high note. A Honolulu Star-Advertiser poll taken a few months before she left office pegged her approval rating at 44/51. As recently as 2006, she had 73 percent approval. (A choice quote from that same article: “Akaka, 86, said he definitely plans to run for a fifth six-year term in 2012.”) I’m surprised she’s eager to run again given that degree of disenchantment. And third, needless to say, Hawaii’s favorite son will be at the top of the ballot in two years so Democrats will be out in even greater numbers than usual. If The One can’t drag a liberal over the finish line there against a mildly unpopular former governor, he’s a one-termer for sure.

Still, a 10 percent chance is better than nothing. And more importantly, it’s going to force Democrats to spend money to defend this seat whereas they probably could have done it on the cheap with Akaka. That means less money to spend elsewhere — and there are a lot of “elsewheres” in 2012. Tell ’em what’s up, Charlie.