Obama, who held the title for a mere two weeks, gained a million followers on his personal Twitter account in five hours. Jenner made the ascension from zero to a million in four hours, confirmed by Guinness World Records.
Jenner's 22-page story in Vanity Fair, which includes photographs from Annie Leibovitz, has been met with encouraging words and praise, including from Jenner's children and step-children.
Jenner was already a well-known figure thanks to her Olympic career (winning gold and setting a world record at the 1976 Games) and reality TV show fame. In an April 2015 interview with Diane Sawyer, Jenner, then identifying as Bruce, announced she was transgender.
Jenner acknowledged her new hordes of followers, even bragging a bit.
"Another Jenner world record, and at 65? Who'da thought! Humbled & honored to have reached 1M followers in 4 hrs. Thank you for your support," she tweeted.
At the time of writing, @Caitlyn_Jenner has upwards of one-and-a-half million followers.