Ken Krimstein has been scribbling since the first grade, when he discovered he could draw a pretty passable Santa Claus.

With the flick of a purple marker and a bit of sleight of hand, a second jolly old bearded guy metamorphosed into — you guessed it — a rabbinical sage in a dark suit and fedora, toting a menorah instead of a candy cane.

The two figures, mounted on a screen at the Oshman Family Jewish Community Center in Palo Alto, stared at each other, their hands gripping overhead straps in a subway.

“I set out to be anything but a doctor. Now I wish I had been a doctor,” Krimstein said, half in jest, during an interview March 6 at the JCC, where he spoke to some 35 people about his new book, “Kvetch as Kvetch Can: Jewish Cartoons.”

“From this you make a living?” he asks himself. Not exactly. Krimstein’s cartoons have graced the pages of the New Yorker, the Wall Street Journal and National Lampoon, but he’s also an ad man and a humor writer, or, as he puts it, “a writer who scribbles.” He never went to art school.

Unassuming, wearing dark-rimmed glasses and with the flaps of a light blue shirt escaping from under his crewneck, the 50-something Krimstein does not look like somebody who would get out of the backroom on the “Mad Men” set. In a business in which image is everything, Krimstein puts his energy into the images he creates.

As he tells it, the Chicago-born writer landed in New York at 22 with a history degree from Grinnell College and a master’s from Northwestern’s Medill School of Journalism. He began his career at the prestigious Ogilvy & Mather ad agency, winning awards for work on such accounts as Hershey’s, Maxwell House and Avon.

Every Wednesday, he would sneak out to deliver his cartoons to the New Yorker. After about 10 years, he received an acceptance, said Krimstein, who “ran through a lot of pens” and papered his apartment with rejection slips.

Today his day job is still in advertising, producing Internet sales reports and other copy, but he continues to craft humor pieces, articles and cartoons.

You don’t have to be Jewish to grasp the humor in “Kvetch as Kvetch Can,” but it helps. Topics include food, identity, family, holidays, culture and guilt, which about covers the gamut, unless you happen to be Orthodox, which Krimstein is not. “I’m somewhere between ‘Jew-Bu’ and Satmar [Chassid],” he quipped.

Krimstein drew upon his two years in Hong Kong for a cartoon in the book labeled “Christmas in China.” The cartoon has Chinese characters on either side of a pagoda, along with a translation: “Let’s order Jewish.”

In one cartoon, a patient gives birth: The caption: “Congratulations, it’s a corporate litigation attorney at a very nice firm.” In another, the headstone of Janice Goldstein says: “Morrie, why’d you have to pick such a drafty spot??!!!”

A cartoon that kick-started the book shows two pigs in a real estate office. The caption: “Actually, we’d feel a lot safer in a Jewish neighborhood.”

Krimstein does live in a Jewish neighborhood, on New York’s Upper West Side with his three children, ages 10 to 17, his wife, a cat, a hamster “and a few roaches we have not been able to get rid of.”

What does he want to be when he grows up? “I want to be a combination of Steven Spielberg, Mel Brooks and Lenny Bruce.” Interestingly, they’re all Jewish.

“Kvetch as Kvetch Can: Jewish Cartoons” by Ken Krimstein (96 pages, Clarkson Potter, $12.99)