ABC13 anchor Samica Knight presented him with a silver ticket late last year to audition before the superstar judges in Austin.
Mills wowed the judges with a performance that ended with Katy Perry, Lionel Richie and Luke Bryan hugging him.
Mills' teachers, classmates and best friends tell ABC13 the support is swelling for this talented student on campus.
"I was like on the verge of tears," said Julyah Williams, Mills' close friend. "I've heard him sing like so much but he was just really, you could feel the passion."
Support for the Houston native has crescendoed. On social media, people predict he will go all the way. His friends have no doubt he will be the last singer standing.
"Oh, Douglas will win American Idol. Of course," said Steven Frisby, Mills' close friend. "He's so talented and he has the fan support, from the media, to the entire school and the entire community behind him."
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