So what do you think, is Frank Lautenberg too old to launch another Senate campaign?

Age is an age-old issue in politics, and a delicate one. It's typically bad form to ridicule an incumbent who has defied the actuarial table, to suggest that such a person should go play shuffleboard or queue up for the early-bird special. On the other hand, when an incumbent hits the golden age of 89 - as Lautenberg did last week - it's not unreasonable to suggest that he may have problems completing a term that would end in 2020. When he would be 96.

The oldster issue has flawed anew in New Jersey, where Newark Mayor Cory Booker is clearly jonesing for Lautenberg's Senate seat, gearing up to challenge Lautenberg in a 2014 Democratic primary. On CNN nine days ago, Booker said of Lautenberg, "He's been there a long time. And I think he's got a decision to make." Booker's actual words were not incendiary, but his inferred message was hard to miss: "Out of my way, old man."

Lautenberg took the bait and told a newspaper, "I have four children, I love each one of them. I can't tell you that one of them wasn't occasionally disrespectful, so I gave them a spanking and everything was OK." That wasn't the wisest of rebuttals. Only a guy pushing 90 would compare a 43-year-old man to a spankworthy child. Whereas, in reality, Booker is already five years older than James Madison was when he drafted the Bill of Rights.

In Lautenberg's defense, there's truth to the cliche that you're only as old as you feel; in his case, maybe 89 is the new 70. He still radiates energy. He worked hard for the Sandy relief bill, and he's indulging his long-held passion for gun reform. On the other hand, New Jersey Democrats appear to be skeptical. According to a new Quinnipiac University poll, 70 percent say that his status as a nonagenarian would impede his job performance; only 24 percent say that his long experience on the job (28 years) trumps all age concerns.

Perhaps most New Jersey Democrats are unfairly "ageist." Or perhaps they're being prudent - given the fact that, if Lautenberg runs again and wins re-election, he would already be 12 years older than the average life expectancy of an American male. He would also be 20 years older than the mandatory retirement age for New Jersey Supreme Court judges. This helps to explain why Booker currently leads Lautenberg by 21 percentage points in a hypothetical Democratic primary matchup.

Jokes and jibes

Our senior incumbents typically get a lot of respect - the average age of a senator is now 62, the oldest average ever - but this is also a culture that worships youth. Which helps to explain the jokes. Once the jokes start, it can mean big trouble. Bob Dole, the 1996 Republican presidential nominee, was widely ridiculed for being 73. (David Letterman said: "A lot of people would look at a glass as half empty. Bob Dole looks at the glass and says, 'What a great place to put my teeth.'") John McCain had the same problem in 2008, at age 71. (Letterman said McCain is "the kind of guy who picks up the TV remote when the phone rings.")

It's rare that an age-challenged politician can summarily squash the age issue - as Ronald Reagan did in his 1984 debate with Walter Mondale ("I am not going to exploit, for political purposes, my opponent's youth and inexperience") - probably because there are few such politicians as deft in their deliveries as Reagan was. Lautenberg's jibe about "spanking" doesn't even come close.

Lautenberg has yet to officially signal that he'll seek a new term. Odds are, he will. He's a feisty, competitive guy, so don't be surprised if he aspires to enter Strom Thurmond territory (Strom served until his death at age 100). But if he takes umbrage about being attacked for his age, he has a big problem. Because he himself invoked the age issue against an opponent back in 1982.

As a young pup of 58, he ran for the Senate that year against Republican Millicent Fenwick, who was 72. He didn't call her an old bat, or anything remotely that blatant, but his code words were easy to read. He called her a "national monument." He questioned her "fitness" for a six-year term. He ran TV ads that featured poor-quality Fenwick photos that accentuated her saggy skin. He later explained, "In campaigns, there are few barriers. The last thing I wanted to do was assault her, but I thought it was important to remind voters of age."

If the reminder was important then, perhaps it is now. New Jersey Democrats are surely aware of what would happen if Lautenberg vacated his seat, for reasons of ill-health or the d-word, during the anticipated second term of Gov. Chris Christie. Under state rules, Christie would probably fill the seat with a fellow Republican.

So don't be surprised if Cory Booker spends the next year talking in code. If he starts thanking Lautenberg for his long years of public service to our country, you'll know it's game on.

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