Millions of television viewers will be worshipping the one and only American Idol tomorrow night, capping the end to Fox's hit talent show competition.

Whittled down from 10,000 original pop-star wannabes, the two finalists are Justin Guarini, 23, of Doylestown, Pa.,  and Kelly Clarkson, 20, of Burleson, Texas, who stand to hold on to true fame while raking in millions in record sales, personal appearances and endorsements over the coming months.

"Whoever wins, wins," Clarkson said.

"It's going to be a lot of fun," Guarini added.

Tonight, the pair will have a final competition, and viewers will cast their vote for their pick via the Internet. The winner is to be announced during tomorrow's show.

The winner gets an album deal with RCA Records, which will release a single on Oct. 16, followed by a CD on Nov. 27. Royalties from the disc could earn the singer, $1 million or more.

The winner could also make as much as $5,000 for each personal appearance at a mall, fair or college campus. And there will also be the opportunity for guest shots on TV shows, which can pay up to $10,000 each.

Either way, the true winner is Fox. The series started out with a healthy summer audience of 11.5 million when it debuted June 11; viewership swelled to nearly 17 million last week as the contestants were pared to the final two.

Fox crows it has the highest-rated summer series among the young adult viewers favored by advertisers.

The number of callers voting for their favorite has swelled to more than 14 million weekly. That includes, however, "power dialers" making thousands of calls in a bid to change the voting outcome — which the producers maintain has had a statistically insignificant impact.

But industry insiders said the winner had better not rest on his or her laurels.

"This program or programs like it are great platforms for a career, but they don't guarantee any career," said Nigel Lythgoe. "Their music, at the end of the day, and where they take their music and the quality of their songs is going to do that."

Billboard's Geoff Mayfield agreed.

"You really can't bet on how someone's going to fare until a record is made and it hits the stores," said Mayfield, director of charts for Billboard. Since artist development is "a gamble and risk anyway," he said, the contestants' chances are as good as any.

Linda Mann, president of Mann Media, a public-relations firm, offered the winner some sobering advice.

"You should try to make as much money as you can as quickly as you can because you'll be on the talent scrap heap tomorrow," Mann said.

But Independent producer 7 Aurelius, who has worked with stars including Mary J. Blige, Janet Jackson and Jennifer Lopez, expressed confidence that the show's best will find success.

"It already worked overseas," Aurelius said, referring to the hit records produced by the three top finishers in Britain's Pop Idol, the model for American Idol.

He pronounced himself ready to work with Nikki McKibbin, 23, of Grand Prairie, Texas, who just missed out on the finals. ("I want to sign her. Print that," said Aurelius.

The Associated Press and the New York Post contributed to this report.

New Corp. is the parent company of Fox and foxnews.com.