He had a bunch of followers before this campaign even started because he used to tweet about a variety of stuff and was a television star.
He had at least over 3 million followers before this campaign started. Her account is also much newer than his. He opened his in 2009 and she opened her in 2013.
The number of followers doesn't matter. The number of active followers does. Look at all those One Direction boys who get millions of likes and RTs daily compared to pop girls with more followers.