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Three years after likable singer/songwriter Kris Allen beat out 1980s fetishist Adam Lambert as the winner of American Idol's eighth season, Lambert continues to best Allen on the Billboard 200.

Released within one week of each other, Lambert's second album outsold Allen's second LP by a whopping 61,000 copies if you compare first-week sales. In terms of chart rankings, Lambert's Trespassing debuted at No. 1—a first for an openly gay male singer—while Idol victor Allen's Thank You Camellia debuted at No. 24. Not to editorialize, but YIKES. In its second week, Trespassing dropped to No. 11 on the charts, selling 22,000 copies (still more than Allen's).

This out-performance mirrors what happened in 2009 when Lambert's debut For Your Entertainment sold 198,000 in its first week, while Allen's self-titled debut—which came out a week before Lambert's—sold only 80,000. As you might have noticed, this means that sales for both artists' sophomore releases are still notably lower than their debuts, which could be accounted for by the fact that albums sold better in 2009 than in 2011.

As a point of comparison, John Mayer is No. 1 on the charts today (May 30) with an album that moved 219,000 copies, which is clearly a much better showing than Lambert's 77,000 copies even if both albums went No. 1.

But returning to Idol, these numbers show what we illustrated in our "Who Is the Most Successful American Idol" post last week: Finishing first on America's most popular TV show doesn't necessarily translate into chart success. But it makes you wonder—if 100 million votes were cast in the season eight finale (split between both singers), why are so few people actually buying the music? Apparently, fans' excitement over a singer as an Idol contestant does not always translate into long-term interest in their career. 

We'll have to wait to see how this year's American Idol winner Phillip Phillips fares on the charts, but we're guessing he hopes his debut sells more like season ten winner Scotty McCreery, whose debut album Clear as Day sold more than one million copies in just over a year.