LOS ANGELES – Jimmy Fallon has convinced Bruce Springsteen to cover "Whip My Hair," Tom Cruise to smash a raw egg on his own forehead and President Obama to "slow jam" the news.

With a record like that, taking over "The Tonight Show" from Jay Leno on Monday should be a snap.

Fallon's ascension to one of entertainment's most coveted spots is intrinsically tied to his ability to talk celebrity guests into ignoring their posses, leaving their egos backstage and getting into the spirit of the most unpredictable party on late-night television.

Call him a fanboy, call him a gusher. He's hosting "Tonight" and you're not.

"I think everyone knows I don't want to make them look foolish. At the end of the day, I want to make them look good," he said last month during an NBC cocktail party held in honor of him and Seth Meyers, who will take over Fallon's post-Leno "Late Night" slot on Feb. 24.

Fallon had just finished breathlessly recounting how he and Springsteen holed up in a tiny dressing room a few days earlier and wrote a "Born to Run" parody aimed squarely at Gov. Chris Christie — whom Fallon warned ahead of time. Hard to imagine any of the competition providing the same courtesy.

"I'm not sneaking up on you and there's no hidden cameras," he said. "I want to let people know they're in on the joke and, in a way, that kind of is the joke."

Fallon's nonthreatening approach has worked, first by giggling his way through "Saturday Night Live" sketches from 1998 to 2004 and then during his five years as Conan O'Brien's replacement on "Late Night." He was so likable that audiences forgave him for taking two years to learn how to conduct an interview.

His return to "SNL" in December to host the Christmas episode drew the show's largest audience in about two years and his final "Late Night" was the franchise's highest-rated episode since 1993. Through it all, he's never lost the ability to look like the luckiest, happiest guy in show business.

"If you're into pop culture, it's a great job," said Fallon, who at 39, still peppers his conversation with words like "awesome" and "crazy." "You get to see movies before anyone else, tickets to any Broadway shows you want. You get to hear great music just 10 feet away from you."

Even a sunny attitude can't hide some daunting challenges ahead.

Leno, the undisputed king in terms of total viewers, lost his beloved gig because the average age of his fans is nearly 58, just outside of the 25-54 demographic coveted by advertisers.

Fallon's base isn't a whole lot younger. Both he and his prime rival, Jimmy Kimmel, average about 50, which is a fairly standard age for the modern-day broadcast network. TBS' Conan O'Brien, who trails the network competition, attracts a viewership that averages under 40, which explains why he's still on the air.

Yes, Fallon pals around with Justin Timberlake and is backed by the Roots, one of music's most inventive bands. But he also showcases artists who mean little or nothing to those in their 20s and 30s. For his final episode, he strapped on a guitar and jammed with 66-year-old blues accordionist Buckwheat Zydeco on Bob Dylan's "On a Night Like This." To close the show, he drummed with the Muppets on the old chestnut "The Weight."

Hip? Sure — in 1975.

"Jimmy's the least exclusive comedian I know," said his producer, Josh Lieb. "He really does want to include the entire country in the conversation."

That may be good news for those of us who like an eclectic meal before bedtime, but it may make NBC executives nervous. They are praying that Fallon drifts toward Taylor Swift and away from James Taylor.

Then there's Fallon's albatross: his monologue.

Those who followed "Late Night" basically endured his mumblefest in anticipation of the show's finely crafted desk pieces, sketches and parlor games. If Fallon were to play to his strength, he'd get past his biggest weakness as quickly as he can and get to the goofy stuff. Instead, he plans to start off with eight or nine minutes of jokes, largely on the advice of — who else? — Jay Leno.

"Jay told me, 'A lot of people work all day, or they work two jobs, and they don't get around to seeing the news,' " Fallon said. "If they happen to miss the news, weirdly enough, they go to you for the news. So you have to have a complete view and make jokes about what's going on so that everyone knows."

But people who want a comic's take on headlines have "The Daily Show" and, to a certain extent, David Letterman, who has slowly transformed from bad boy to traditionalist.

Could Leno be offering terrible advice in the hopes that Fallon will fail and he'll be called back into duty, much as he was when "The Tonight Show" ratings tumbled under O'Brien? Time will tell.

What Fallon can — and should — offer is a natural giddiness that everyone else in late night is too cool to display.

"Steve Allen was the first guy to sit in a plate of ice cream and pretend he's a banana split by rolling around in chocolate syrup," said Fallon, referencing the "Tonight Show's" original host back in the 1950s. "That's what it should be. It should be goofy and fun."

Goofy and fun. That mantra should be carved into the wall so Fallon sees it every time he steps on stage. If he forgets that formula, he won't be swimming in dessert. He'll be drowning.

NealJustin@startribune.com • 612-673-7431 • Twitter: @NealJustin