Among the Republican presidential candidates, only Vivek Ramaswamy had his own account. He dropped out of the race last month.
The app, once known for viral dance videos, has increasingly become a source of news and information, particularly for younger Americans. About 14 percent of U.S. adults said they regularly got news from TikTok last year, up from 3 percent in 2020, according to the Pew Research Center.
Last month, campaign officials celebrated when a TikTok video made by a North Carolina teenager whose home Mr. Biden visited drew millions of views on the platform.
Whether the Biden campaign can make the 81-year-old president look cool on the platform remains an open question. In the Sunday post, Mr. Biden wore khaki pants and a blue quarter-zip sweater with a microphone clipped to the zipper. The questions came from Rob Flaherty, a deputy campaign manager, according to a campaign official.
The post had received 4.5 million views by Monday morning, according to TikTok.
While TikTok does not allow paid political advertising, several campaigns have successfully used the app to build a rapport with potential voters and to help win races. Senator John Fetterman, Democrat of Pennsylvania, for example, counted TikTok among the tools he used to beat Dr. Mehmet Oz in the 2022 midterm elections.