(CNN)For as many foes as the superhero fends off, Batman has a formidable team of supporters starting with his sidekick Robin, Gotham City Commissioner James Gordon and his ever-loyal butler, Alfred Pennyworth.
But one of the Caped Crusader's most fervent supporters lies not in a comic book, but in the US Senate, and he's known the Bat for more than 80 years.
Sen. Patrick Leahy, a Democrat from Vermont and the longest-serving member of the current Senate, is a Batman aficionado who's turned his fandom into philanthropy. He's even used the comics to forward his legislative agenda.
Now President pro tempore of the Senate, Leahy is third in the presidential line of succession. Though it's unlikely he'll ever have to serve as President, his high-profile position shines a brighter light on his colorful resume -- which includes multiple appearances in the "Batman" films.
When he's not working in the Senate chambers in Washington, Leahy retreats to Gotham, where Batman fights cartoonish villains and mans the Batmobile. It's a comfort he took up when he was 4 years old.
"If you live in the real world all the time, it can be kind of boring," the senator told Vermont alt-weekly newspaper Seven Days in 2008.
When Leahy met Batman
Leahy declined an interview for this story through his spokesman, but his affinity for all things Batman is well-documented. As he wrote in the foreword of "Detective Comics: 80 Years of Batman," he was born just one year after Batman's first comic published in 1939.
He first discovered Batman at age 4, when he received his first library card. He frequented the Kellogg-Hubbard Library in Montpelier, where he spent many an afternoon poring over comics. While his school friends raved over Superman, Leahy found a "kindred bond" with the Bat.
Sen. Patrick Leahy visits the Kellogg-Hubbard Library in 2008, where he fell in love with reading, to discuss comics and his role in "The Dark Knight."
"Entering Batman's world through my imagination opened an early door into a lifelong love of reading," he wrote in his foreword.
He'd continue spending hours at the library each day until adulthood, and even after he moved to Washington, he'd make time to pop in. He's a vocal advocate for literacy and the preservation of libraries so children can have similarly formative experiences with books.
"Some of my fondest memories as a child were at the library, where everyone fit in and possibilities were limitless," he writes on his Senate website.
Leahy's appearances from page to screen
Leahy was elected to the Senate in 1974 and until the mid-1990s, his affinity for Batman didn't have much to do with his duties on Capitol Hill.
That changed in 1996, when Leahy collaborated with DC Comics to create "Batman: Death of Innocents: The Horror of Landmines," a graphic novel warning of the dangers of landmines. Leahy has long advocated to end the use of landmines, and he told the Capitol Hill newspaper Roll Call that he placed copies of the comic on every senator's desk that year.
Leahy's first foray into screen acting -- something he does strictly when Batman is involved -- came in 1995, when he appeared in the critically reviled "Batman Forever." The same year, he voiced a character billed as "Territorial Governor" in "Batman: The Animated Series."
Leahy, scowling, berates someone off-screen in his role as a board member of Wayne Enterprises in "The Dark Knight Rises."
Since then, Leahy has appeared in nearly as many "Batman" films as the Caped Crusader himself. He usually appears as a scowling politician (though in "Batman & Robin," which his son Mark also had a cameo in, he was allowed to enjoy a raucous party). He even met an explosive end as the curiously named Senator Purrington in "Batman v. Superman: Dawn of Justice."
"I explain to everybody that getting blown up was OK 'cause my wife's a registered nurse," he joked to Roll Call in 2016. "She put me back together and I never missed a vote."
His most notable cameo, though, came in 2008's "The Dark Knight," when he confronts Heath Ledger's Joker and famously tells the villain that he's "not intimidated by thugs." The Joker, true to form, responds by grabbing Leahy's character and menacing him with a knife.
Ledger, who died before the film's release, is Leahy's favorite Joker.
"He scared the heck out of me, when he came at me with the knife," he told Roll Call. "I didn't have to act."
Leahy, shown here with actor Holly Hunter, aptly portrayed a senator in "Batman v. Superman: Dawn of Justice."
He'll be absent from the upcoming reboot "The Batman," starring Robert Pattinson in the titular role. Citing a busy schedule, he told the Burlington Free Press he "didn't even seek to be in it."
"I have too many other things going on with Covid, with appropriation bills," he told the paper in August.
While his film roles have certainly satisfied his inner fanboy, Leahy does it for the library where his love for reading bloomed. He donates every fee from his appearances and royalty checks from residual showings to his beloved Kellogg-Hubbard Library, where he helped finance a children's wing named for him. From his roles in "The Dark Knight" trilogy alone, Leahy has donated more than $150,000 back to his hometown library, said Carolyn Brennan, co-director of the library.
In 2012, the library hung a plaque honoring Leahy, who staff called their "super hero."
Why Leahy loves Batman so
Leahy found Batman when he was a boy, but his love for the fictional hero is foundational to who he is and the lawmaker he became. Batman instilled in Leahy a love of reading and promoting literacy and of delivering justice (though as a government servant, not a caped vigilante).
A plaque for Leahy hangs in the Kellogg-Hubbard library, a public library in his hometown of Montpelier, Vermont.
Leahy preferred Batman to other characters because, unlike the god-like Superman or the super-powered Spider-Man, Batman was just a man, albeit an extremely rich one, with "human strengths and human frailties." The danger Batman faced was different than that of other heroes -- his felt real, Leahy wrote in the DC collection foreword.
"The Batman prevailed through superior intellect and detective skills, through the freedoms afforded by great wealth and through sheer will," Leahy wrote in his foreword. "Not superpowers, but skill, science and rationality."
Much like Bruce Wayne, Leahy is just a man, albeit one with more power than most and the chance to make real, tangible changes in his own Gotham. Following Batman's example, he's vowed to use that power wisely.
