Summer Fan Showdown is a month-long competition on PopCrush to determine this summer's most dedicated fan base.

No one knows more about loyalty than Beliebers: Justin Bieber's longtime fan army have been through it all — from the heights of fame to the, well, lower moments. But through it all, they've stayed fiercely protective of the Purpose crooner, who has demonstrated that he can rise above and continue to share his craft with the world. But will his faithful followers push him through to the next round of the Showdown?

On the other hand, there's TWICE — South Korea's hottest girl group export at the moment. Month after month, the troupe ranks highest as the most recognizable brand in the country, and it's easy to see why: with infectious bops like "TT," "Knock Knock" and "Signal" at hand, they've smashed the charts with their bubbly charm and cutesy choreography. But will their fanclub, ONCE, get TWICE rolling right through to Round Two?

The battle starts now: place your vote between Justin Bieber and TWICE. This round ends on June 9 at midnight.

This poll is now closed. Head over to Round 2!

Join the conversation on social media! Use #SummerFanShowdown to discuss this year’s competition.

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