Many would argue that Carrie Underwood is the most successful singer to ever be on American Idol. It looks like Forbes magazine just made it official.

According to a ranking published by Forbes on Thursday, July 21, Carrie Underwood earned an estimated $20 million between May 2010 and May 2011. The pretax sum makes Underwood the top earner among all of the show's former contestants.

Underwood won the competition back in 2005. Singers Adam Lambert and Chris Daughtry both tied for second on the Forbes earnings list, each of them earning about $6 million.

Other country-related Idol artists on the list include original Idol winner Kelly Clarkson in sixth place with $2.5 million and Kellie Pickler in eighth place with $1.8 million.

One interesting statistic the report indicated was that Idol host Ryan Seacrest made a whopping $61 million, which is a higher sum than all 10 Idol stars' incomes combined.

Is Ryan Seacrest really worth $61 million a year?