This was the debut single released by American Idol Season 3 winner Fantasia Monique Barrino, who records as Fantasia. The inspirational song was written specifically for the show by first season Idol finalist Tamyra Gray along with Sam Watters and Louis Biancaniello. The finale matched up Barrino with Diana DeGarmo, and each performed this song. The results were announced on the show the following night, and when Barrino won, she performed it as her victory song.

Thanks to exposure on American Idol and a big marketing push, this song debuted at #1 on the Billboard Hot 100 chart. In years past, it took a while for new artists to make their way to the top of the charts, but Idol changed that: Season 1 winner Kelly Clarkson took just two weeks to reach the top with her first single "A Moment Like This," and the following year, runner-up Clay Aiken went straight to the top with his debut, "This Is The Night," beating out winner Ruben Studdard, whose single "Flying Without Wings" placed at #2. This made Aiken the first new artist to debut at #1 on the chart, and when Fantasia did it, she became the second.

Clarkson and Aiken each stayed for two weeks at the top, but Fantasia dropped off quickly, and "I Believe" became the chart-topper with the fewest weeks in the Top 10, namely two, when it dropped 1-6-18. The old record of three weeks belonged to John Lennon's "Whatever Gets You Thru the Night," which fell from 2-16 in November 1974.

The song was the Billboard Top Selling Single of the Year of 2004.