In a list compiled by Twitter of the most tweeted about celebrities in 2012, Justin Bieber took the No. 1 spot.  

His message to a young fan that passed away in September was also the most re-tweeted pre-election message of the year. The "Beauty and a Beat" singer posted "@justinbieber RIP Avalanna. i love you" on Sept. 26, and it had a total of 223,771 retweets.

"That tweet was something beyond his music. It was him and his fans saying goodbye to one of their own and it clearly resonated with folks," Twitter senior manager Rachael Horwitz said.

After the election results aired, the top tweet that generated the most re-tweets for the year was President Barack Obama's message "Four more years" posted on Nov. 6. 

After breaking it down by categories, Rick Ross was the most tweeted hashtag in music, followed by "#hiphop," Trey Songz as No. 3 and Nicki Minaj as No. 4.

The Olympic Games was the most tweeted about single event of the year. The 16-day games in London generated 150 million tweets and the closing ceremony, specifically the Spice Girls' performance, gathered the largest Games-related spike with more than 116,000 tweets per minute. The largest competition-related conversation, part of the London Games, was when Jamaica's Usain Bolt (@UsainBolt), the most-discussed athlete, won gold in the 200-meter sprint. That single event produced 80,000 tweets per minute. 

The second most tweeted about event of the year was the U.S. presidential elections - the first debate produced 10 million tweets - and No. 3 was the MTV Video Music Awards. The show itself produced 14.7 million tweets but the biggest spike of the night (98,307 tweets per minute) happened when One Direction won Best Pop Video. The second biggest spike of the night was Taylor Swift's performance.