Ed Sheeran, Kendrick Lamar and Bruno Mars are vying for top honours at the American Music Awards.
Mars leads the way with eight nominations, including artist of the year, at the star-studded event in Los Angeles on Sunday where fans vote for the winners.
Lamar, Sheeran, Drake and The Chainsmokers are also competing for the top honour and have five nominations apiece.
James Arthur and former One Direction singer Niall Horan are among the contenders for the new artist of the year award.
Selena Gomez is set to make her first performance since she had a kidney transplant when she takes the stage at the Microsoft Theatre.
Pink and Kelly Clarkson will open the show together in their first live collaboration and Lady Gaga will also perform.
The nominations are overwhelmingly dominated by males, with no women being selected for top categories including artist of the year, video of the year or tour of the year.
Halsey criticised gender balance as a “missed opportunity”, adding she was “really disappointed to hear near exclusively male names”.
She received two nominations for her collaboration with The Chainsmokers on Closer but is not up for a solo award despite having a number one album in the US this year.
The nominations are based on music sales, radioplay, streaming figures as well as interactions on social media and tours, according to the organisers.
Diana Ross will be presented with a lifetime achievement award and hosting the event is her daughter, Black-ish actress Tracee Ellis Ross.
The ceremony is set to begin in LA at 5pm on Sunday (1am on Monday in the UK).