SOMETIMES, however rarely, the outlier manages to gain an inside track. And perhaps no first-time Pulitzer finalist has ever been more of an outlier than Dan Perkins.

This week, of course, Buffalo News journalist Adam Zyglis won the Pulitzer Prize for Editorial Cartooning, and Kevin “Kal” Kallaugher of the Baltimore Sun and the Economist was a finalist. Neither was a surprise, especially given the string of honors that the two had picked up in recent months. (If anything, a few industry-watchers were surprised to realize that Kal, in his four decades at the board, had never been a finalist before.)

And then there was Perkins, who, as creator of the comic “This Modern World,” goes by the nom-de-toon Tom Tomorrow. He’s that rare alternative or independent cartoonist who gets the call. Just how uncommon? So much so that his selection this year even surprised him. As Perkins tells The Post: “I really didn’t ever think I was going to get a finalist nod.”

In honoring editorial cartooning, the Pulitzer Prize Board has historically been a tradition-bound group. To the degree that whenever a name bobs up from beyond the mainstream, it feels like a breakthrough. In the category’s nine-decade past, in fact, you can count on two hands the number of winners who weren’t closely affiliated with a single mainstream newspaper, typically as a full-time staffer.

Which is why Perkins tells The Post’s Comic Riffs: “I felt that for a long time, I probably wasn’t up for consideration.”

On a handful of occasions, the winner has emerged not from the portal of a newspaper perch, but strictly from a syndicate. Breaking form in the ’40s, the Pulitzer jurors honored two syndicated non-staffers that decade, and both became legend: Herblock of NEA in 1942, before he would win two more with The Washington Post: and Sgt. Bill Mauldin of United Feature Syndicate in 1945 — and all he did was become the cartoonist most singularly identified with G.I. life during World War II.

It would be three more decades before the Pulitzers again made an exception, when in 1975, Garry Trudeau‘s oft-political “Doonesbury,” distributed by Universal Press Syndicate, became the first comic strip to win the Prize. And that helped pave the way for two more comic-strip artists to win in the decade that followed: Jules Feiffer of the alt-weekly Village Voice in 1986, and “Bloom County” creator Berkeley Breathed of the Washington Post Writers Group in 1987. With three outliers nabbing Pulitzers within 12 years, it felt as though a philosophical shift were afoot.

Turns out, though, that was indeed just a feeling. In the nearly three decades since, only two cartoonists have won the Prize through non-staff channels: future Post cartoonist Ann Telnaes of Tribune Media Services in 2001, and self-syndicated Mark Fiore in 2010. Fiore became not only the first cartoonist to receive the Prize entirely for animations, but also the first to win for work that appeared exclusively online (

Since cartooning finalists began being named in 1980, the list of non-staff and/or alternative artists has included Feiffer, Trudeau, Henry Payne (Scripps Howard News Service), “For Better or for Worse” creator Lynn Johnston (Universal Press Syndicate). Ted Rall (Chronicle Features), “Funky Winkerbean” creator Tom Batiuk (King Features) and Matt Bors (Universal Uclick).

All of which makes Perkins perhaps the Prize’s biggest outlier since Feiffer in the ’80s. Perkins, who is self-syndicated, entered cartoons that were published on the Daily Kos, which, as the cartoonist himself notes, “is a blog.” (His work also appears on The Nation.)

“I’ve been doing this for 25 years,” says Perkins, who launched “This Modern World” in the early ’90s, “and certainly for 20 of those years, I was not realistically eligible, because I was an [alternative] outlier.”

Not only did Perkins’s work appear mostly in alt-weekly papers most of those years, but his format is as a text-heavy, multi-panel feature — far from the single-image format that the Pulitzer jurors generally favor.

“You’ve got judges who weren’t super-familiar with my field,” Perkins tells The Post’s Comic Riffs. “They looked at this vast trove of submissions and then they looked at mine and thought: ‘What the hell is this?’ ”

“Also with the format, it’s so word-heavy that you have to sit down and [really] read it,” Perkins notes. “It’s not a thing you can glance at and decide if you like it or not. It can be hard to get people to sit down [during mass judging] and take it in.”

Working in Perkins’s favor in recent years, however, has been not only publishing on a blog outlet, but also the recent recognition of his work elsewhere, including the less tradition-bound Herblock Prize, which has recently honored three alternative/indie cartoonists: Perkins, Bors and Jen Sorensen.

“It’s been gratifying to have the work recognized in the past couple of years,” Perkins says. “I got the Herblock, I got a Society of Illustrators silver medal, and now this — it’s just nice to have these things.”

He also notes of the growing recognition: “There are a number of editors who have been reading this [feature] half their lives.” So does this mean multi-panel cartoons from non-traditional outlets are gaining in Pulitzer acceptance? “I didn’t quite [get] the brass ring, but it will happen for someone within the next 10 years — who will win — no question in my mind.”

Perkins, who is in his mid-50s, just doesn’t know whether it will be him.

“I don’t know that I’ll be doing this when I’m 80,” Perkins tells The Post. “Time is not my friend. How many more years will I be eligible? I don’t have that many more shots at it.”

“But,” he quickly adds, “even to have made it as a finalist — this is hugely significant for me. … I’ve been waiting for this for a long time.”