Alice Walker’s 1982 novel “The Color Purple” follows the story of a woman struggling to find herself amid racism, beatings, and rape. The tale might not immediately bring to mind jazz hands, but in the most recent advertisements for the Broadway adaptation, a grinning former “American Idol” winner, Fantasia Barrino, seems just on the verge of ecstatically breaking into jazz hands to celebrate the production.

Such is the slightly uncomfortable relationship between “American Idol” and Broadway. As former contestants populate musical theater stages with increasing frequency, it is hard to imagine that the tension will go away any time soon.

With the incorporation of former “Idol” contestants on Broadway — including, most recently, Tamyra Gray, who will begin performances in “Rent” next week — it is becoming clear that the pop charts are not the only places that the presence of “Idol” can be felt. Bernard Telsey, whose company Bernard Telsey Casting, Inc. has cast former “Idol” contestants in numerous Broadway shows, views the reality contest as another form of casting call for his company. “We’re probably the only office in town that is happy when someone loses on ‘American Idol,'” he says.

The runner-up in Ms. Barrino’s season, Diana DeGarmo, appeared as Penny Piggleton in “Hairspray.” Like Jennifer Hudson, who earned a role in “Dreamgirls” after many people felt she was prematurely ejected from “American Idol,” the controversial early outcast Frenchie Davis was well received as a soloist in “Rent” on Broadway.

Constantine Maroulis starred in the musical adaptation of “The Wedding Singer.” From season three of “American Idol,” contestant Katie Webber is in the cast of “Wicked” and Josh Strickland has starred in “Tarzan” since its premiere in May of last year. The fourth place singer from the fourth season of the show, Anthony Fedorov, began performances as Matt in “The Fantasticks” on May 1.

The deluge of massively popular “Idol” influences on Broadway has been a boon for the bottom line.

In her first week on Broadway, Ms. Barrino helped “The Color Purple” take in $1.2 million in ticket sales and broke the record of sales for both the Oprah Winfrey-produced musical and the Broadway Theater. And despite the strange ambivalence of the posters, Ms. Barrino puts in a respectable performance as Celie.

Ms. Barrino may even be better suited to play the role of Celie than LaChanze, the Tony Award-winning actress who originated the role. LaChanze is a talented singer known for her good looks. Celie is a character frequently told “you ugly,” and Ms. Barrino is an unconventional looking woman whose beauty shines through most when she is singing. This makes her a natural fit for a coming-of-age story of a woman finding herself through song.

The televised contest of “American Idol” rewards vocalists who can power through various ballads, but in the civilian world, former contestants seem to do best when they pair their singing talent with their personal story line. Ms. Hudson won an Oscar for playing overlooked singer Effie White, whose saga hewed closely to her own dismissal from “American Idol.”

Similarly, Ms. Barrino has much in common with Celie, a character who is raped by her stepfather and treated as a slave by her husband. Raped in her youth and impregnated at 16, Ms. Barrino was effectively illiterate when she competed on “American Idol.” She published a New York Times best-selling autobiography “Life Is Not a Fairy Tale” in 2005 and starred in a Lifetime Original Movie based on the book last year.

Ms. Barrino has a much more nuanced and sultry voice than many of the other singers emerging from FOX’s reality contest. The music from “The Color Purple” does not often capitalize on her talents, burying much of the score under a lifetime of plot points that need to wiz by in under three hours. Ms. Barrino only gets to shine in the final moments of the musical, when Celie overcomes the obstacles of her life and begins to find herself.

Though they might not have the experience or depth of many Broadway stars who made their name the hard way, the contestants of “American Idol” have proven that they can sing and get people in seats. With the financial difficulties of keeping Broadway shows afloat, producers could do much worse for their bottom line. Often big television and movie names with untested singing skill are brought to boost Broadway shows. The cast of “Chicago,” for instance, has had visits from everyone from Lisa Rinna, Melanie Griffith, and Brooke Shields to now Joey Lawrence.

After the originating talent leaves a show, it takes more than a little effort to keep the production financially viable. Bringing name singers in helps ticket sales, even if it means passing over traditionally trained actors in favor of stunt casting.

As shows like NBC’s “Grease: You’re the One That I Want” and the BBC’s “How Do You Solve A Problem Like Maria?” have proven, reality television can be a fertile casting opportunity for Broadway and spark public interest in the shows.

Ms. Barrino’s role in “The Color Purple” may betray a truth about “American Idol.” Though the contest displays a democratic element missing from much of the pop music industry, the contestants are not always marketable as chart topping pop singers.

Rather than producing breakout pop stars as intended, Simon Cowell’s show and its ilk may be better equipped to introduce the world to working character actors and actresses, much to the frustration of aspiring singers and actors who haven’t gone the reality television route.