Update: Britney Spears won this round. Click here to vote for her Britney Army in the Semi-Finals!

Alright, fans. Let's get ready to rumble! This year's March Madness is seeking the best fanbase, so each week we're pairing up artists to find our which fandoms are the most devoted. Round 1 features Britney Spears' Britney Army versus Adam Lambert's Glamberts. Who do you think is the best fanbase?

Britney Spears' fans stuck by her side since she shimmied onto the music scene in 1998. While Brit's career is full of highs -- like her Las Vegas residency and her insanely impressive music catalog -- there's no doubt that she's experienced some lows as well. Nevertheless, her loyal Britney Army stuck by her side through all of it, supporting her in every way possible. Now that's the definition of devoted.

Of course, Adam Lambert's Glamberts are pretty darn supportive as well! Adam charmed music lovers everywhere when he appeared on Season 8 of American Idol. The singer quickly proved to be a formidable presence in the music industry, releasing a slew of hits and even joining Queen on tour. Throughout all of this success, Adam continues to grow his Glambert fanbase, all while continuing to spread a message of acceptance through his activism.

Which fanbase is the best? You can vote once an hour until the polls close at 3PM ET on March 17.

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