Justin Bieber remains her closest rival in terms of Twitter popularity, currently boasting 8.4 million fans. He is also expected to hit nine million in the coming weeks. After Bieber and Spears, Barack Obama and Kim Kardashian lay claim to the most followers. To mark her birthday, Gaga has posted a quirky photo on her microblogging page saying 'Happy Birthday to me'.
Beneath the photo she posted: "Drawing on table at restaurant. If I had to give it all back, but got to keep my fans, that'd be ok." Last year, Gaga marked her 24th birthday with a topless picture for fans, who she thanked for all their "beautiful" messages.