In its early days, “American Idol” launched the careers of several unknown singers whose CDs shot up the charts as soon as they were released. Alas, that was then; this is now, and the show’s commercial momentum has diminished along with its freshness as a piece of entertainment. We rate the best and worst Idols.

BEST

CARRIE UNDERWOOD

The season 4 winner has 5 Grammys and a voice that will last a lifetime. In 2009, Forbes reported she is the top earning “Idol” alumni.

JENNIFER HUDSON

The rejected “Idol” contestant proved the voters wrong by winning an Oscar for “Dreamgirls.” She hasn’t sold as many records as the other contestants, but do they have an Academy Award?

KELLY CLARKSON

She’ll always be first, the young woman who helped put “Idol” on the map. Her powerhouse voice has netted 2 Grammys, 4 American Music Awards and worldwide sales of 23 million.

CLAY AIKEN

The choir boy shoulda won in season 2 and proved it when his first record, “Measure of a Man,” sold 613,000 copies in a week, still an “Idol” record.

CHRIS DAUGHTRY

Kicked off in a shocking upset, Daughtry proved the season 5 voters wrong by going on to win 4 American Music Awards and releasing the fastest-selling album in rock history, “Daughtry.”

WORST

TAYLOR HICKS

The first sign that “Idol” was in trouble happened when this unbearably corny country crooner beat Chris Daughtry and Katharine McPhee in season 5.

KRIS ALLEN

Won the season 8 contest in the most controversial voting result since season 2, when Ruben Studdard beat Clay Aiken. Since his victory over Adam Lambert, Allen’s career has not taken off.

LEE DE WYZE

If Lee DeWyze’s season 9 victory was a symbol of the future of “Idol,” this show was really in trouble. DeWyze’s debut album only sold 102,000 copies in its first week.

SANJAYA MALAKAR

So cheesy he gave rise to a Web site, votefortheworst.com, that encouraged people to vote for his Velveeta performances and made “Idol” a laughingstock.

FRENCHIE DAVIS

Topless photos? Seriously? The well-endowed Frenchie, who made it to the semifinals before she was disqualified, was a headache “American Idol” did not need.