Kimberley Locke, second runner-up on last season's "American Idol," is sitting in a dressing room backstage at the television talk show "The View," waiting to perform her first single.

The song, "8th World Wonder," is the first post-"Idol" single to debut at No. 1 on the sales charts, and her "View" appearance is one stop on a victory lap that is a powerful testament to the mighty reach of "Idol," which now regularly attracts 20 million viewers per show.

Locke's current success might seem the predictable spoils of an ex-finalist. But in reality, she's the first contestant outside of Kelly Clarkson, Ruben Studdard and Clay Aiken -- the triumvirate that has emerged from the show's first two seasons -- with a real shot at A-list success.

"Idol," which will crown its third-season champion tomorrow night, has so far produced two multi-platinum-selling superstars (Clarkson, Aiken), one star (Studdard) and one trivia question (William Hung, the tone-deaf entrant whom America briefly embraced). It has also proved a reliable platform to launch other contestants from complete obscurity to the semi-obscurity of Canadian productions of "Hairspray" or hosting gigs at the TV Guide Channel.

Still, some of the "Idol" also-rans, including Locke, are setting their sights higher. As she and several distant runners-up prepare to release their first CDs, the depth of the show's star-making power will be tested for the first time.

In some ways, the math favors the singers. After all, considering the size of the "Idol" viewership, a contestant's CD can go platinum if only 5 percent of the audience buy it. But many talented contestants fell by the wayside before a CD ever got made, and when "Idol" alumni with recording contracts are asked why that happens, the answer is usually the same: They just didn't want it badly enough.

Four who do want success badly, and will soon have new CDs to show for it, are Locke, Tamyra Gray (Season 1, fourth place), Christina Christian (Season 1, sixth place) and Joshua Gracin (Season 2, fourth place). They all underwent a lengthy, arduous process that began after their respective season finales.

In exchange for the head start of having appeared on the show, "Idol" contestants must relinquish a lot of control over what happens to them afterward.

They must sign extensive contracts with 19 Entertainment, the powerhouse British management and production company that originated the show. After a season's 12 finalists -- winnowed by judges and audience members from an initial field of perhaps 10,000 aspirants -- return from a lengthy postseason arena tour, 19 Entertainment (and "Idol"-affiliated labels, such as RCA) decide whether to pick up a contestant's option; only winners are guaranteed recording contracts. If the label passes, and it usually does, contestants are free to look for a deal elsewhere. But once they sign with another label, record an album and do the requisite pre-release promotional work, a momentum-killing amount of time may have passed.

Locke attributes her first-out-of-the-box success to the acumen of her business team and the eagerness of her new label, but her rapid and relatively painless extrication from "Idol" likely had something to do with it.

"I went in knowing what I wanted out of it," says Locke, who signed a deal with Curb Records almost immediately. "I wanted a recording contract. I didn't care if I won 'American Idol.' I wanted to get as much exposure from the show [as possible] so I could do what I wanted to do. Other people, maybe they had other things in mind. Maybe they really didn't want to sing."

Neither talent nor one's place in the final ranking is a reliable indicator of post-show success. Gray, whose unceremonious ouster is still seen by many as the show's greatest indignity, is on her third record label, having been passed from RCA to J Records, from which she was subsequently dropped. 19 Recordings, a new label affiliated with 19 Entertainment, is set to release Gray's debut, "The Dreamer," today -- almost two years after she was voted off the show. The equally beloved Christina Christian, who signed to 19 after similar difficulties, plans to release her as-yet-untitled album in Europe this summer, with an American release date tentatively planned for later in the year.

Niche contestants such as RJ Helton, who released a Christian pop album, "Real Life," in March (and who is managed by Mathew Knowles, father of Beyonce), and Gracin, the Marine whose self-titled country debut will be released in mid-June, often fare better than contestants with more mainstream commercial appeal. Expectations are lower and, unlike with contestants who land at "Idol"-affiliated labels, career interference is often minimal, ensuring a speedier release date.

"I told [label executives] I was singing country music," says Gracin, whose new single, "I Want to Live," is a top-20 country hit and still rising. "I don't know if that had anything to do with it, but they wound up passing. I think it helps [being a country singer]. There's so much competition in pop and R&B, it's hard to break into."

Record industry insiders point out that while "Idol" offers contestants invaluable publicity, hit singles have an ineffable calculus all their own. Talent and exposure are necessary components, but more subjective qualities like charisma and determination matter almost as much.

Unlike conventional artists who spend years honing their craft and pursuing a record deal, many contestants find themselves on "Idol" almost capriciously. (Studdard, for example, intended only to keep an auditioning friend company but wound up trying out himself.) Many contestants aren't particularly interested in making records; others simply aren't seasoned enough, or are still unsure what style of music they want to sing. Any ex-contestant working cabarets and state fairs, the thinking goes, is exactly where he should be.

"The whole process of signing, marketing and promoting an artist is an extremely expensive one," notes 19 Entertainment Vice President Tom Ennis. "To make that leap of faith, [labels] don't just do that because someone came in ninth on 'American Idol.' If the economics of the record business were a little different, I'm sure they all could do well."

While most ex-contestants haven't landed record contracts, the chart performance of Locke's and Gracin's singles suggests that anyone who has can expect at least a moderate level of success. Factor in sales figures for Clarkson, Aiken, Studdard and the countless contestant compilation albums, and the show's track record looks even more impressive.

The first CD by first-season runner-up Justin Guarini, overlooked amid the hype surrounding Clarkson, and the cringe-inducing movie "From Justin to Kelly" have been the only "Idol"-related flops so far. Guarini has since been dropped from his record label.

"Overall music sales are down. If you're a record executive, you have to be happy with all the cumulative success [of "Idol" product]," says David Adelson, music correspondent for E! Entertainment television. Adelson says that while it wouldn't hurt for the show to establish a deep roster of hitmakers, that isn't necessary to continue its popularity. "It's a TV program before anything else. The primary priority is to create a hit television show. Everything else is gravy."

Industry experts -- and many of the ex-contestants interviewed -- cite La Toya London, who was voted off the show May 12, as the 2004 finalist most likely to succeed. If she or any of the ex-"Idol" candidates, who rival Miss America contestants in their ability to stay upbeat and on message, are worried they're more likely to become the next Kimberly Caldwell (currently representing "AI" perfume at JC Penney) than the next Kimberley Locke, they're not saying.

Achieving stardom "all depends on who you have backing you and who supports your ideas and vision," says Gray. "But 'American Idol' is a great vehicle. I'm so glad I had it."

"Idol" also-ran Kimberley Locke's "8th World Wonder" debuted atop the chart.Kimberley Locke's was a runner-up on "Idol" last season. Now she's one of its success stories.