At least one Democratic Senator is going to have to face a strong primary challenge this year, but it's not (yet) the one you're thinking of. In Hawaii, Representative Ed Case has tossed his lei into the ring in an effort to unseat the 81-year old incumbent, Daniel Akaka. With a popular GOP incumbent governor, having two octogenarian Senators is increasingly risky for the Democrats, putting at risk any chance the party might have of recapturing (and keeping control of) the U.S. Senate over the next four years.

Case, however, is from the Lieberman "New Democrat" school, with an ambitious streak to boot; after running (and losing) a run for governor in 2002, he won a special election to fill the seat of the late Patsy Mink in 2004, defeating her widower. Having him replace the dependable liberal stalwart Akaka (who himself was appointed to replace a deceased Senator, Spark Matsunaga, in 1990) would be a bitter pill to swallow. Chalk it up to the perils of gerontocracy.