Less than a week after joining TikTok, former President Donald Trump’s following on the app has dwarfed those of his opponents in the presidential race, with his account racking up 5.6 million followers and amassing more than 87 million views on his first video.

An account for President Biden’s campaign has 360,100 followers. Independent candidate Robert F. Kennedy Jr., who joined the platform before either major candidate, has 1.3 million followers. 

The presence of both major party candidates on TikTok underscores its role in helping campaigns connect with young voters ahead of November’s election. While one third of Americans are on TikTok, 62% of 18- to 29-year-olds say they use the app, according to the Pew Research Center. New polling shows that Mr. Biden has a narrow margin over Trump among Americans aged 40 and under. Across battleground states, voters under 30 are less likely than older voters to say they will definitely turn out this year. And those who are likely to vote are more likely to be considering third-party candidates.

Their TikTok accounts also bring into focus the complicated relationship both have with the app. As president in 2020, Trump attempted to ban the platform with an executive order that was halted by the court. He recently changed his stance and said he opposes a ban. 

In April, Mr. Biden signed legislation that would either force TikTok’s Chinese owner ByteDance to sell the platform or face a ban in the U.S. The president does not have an individual personal account or an official White House account, but his campaign launched a “Biden-Harris” account in February. RFK Jr. has been outspoken in his opposition to a TikTok ban.

Kennedy and Trump’s popularity on TikTok is unique among politicians. Only two sitting members of Congress — Democratic Rep. Jeff Jackson of North Carolina and independent Sen. Bernie Sanders of Vermont — have more followers than Kennedy, and neither have as many as Trump.

Recent polling indicates that Kennedy is performing well with young voters, many of whom are on TikTok. A New York Times/Philadelphia Inquirer/Siena poll in May found that 26% of Kennedy’s supporters said they use TikTok often, more than both Mr. Biden (15%) and Trump (14%). Eighteen percent of those polled under 30 said they support Kennedy over Trump or Mr. Biden.

Mr. Biden’s campaign launched a TikTok account in February, but hasn’t achieved the same reach as Kennedy. The campaign’s videos have on average gotten half as many likes and three quarters as many views as Kennedy’s. 

Campaign accounts across social media platforms typically achieve less traction than individual accounts. The Biden campaign chose to launch their account “to use every tool we have to reach young voters where they are,” a campaign official said, adding that the reelection effort has “hired dozens of staffers who are working every day to develop content” for its social media accounts.

When asked why the Trump campaign decided to join the platform now, spokesperson Steven Cheung gave a similar reason, writing that “Team Trump will leave no front undefended,” and that the account is another step in their effort to reach young voters. 

Trump’s overnight success on the platform mirrors a trend TikTok’s own researchers have reportedly observed: over the past several months, there has been twice as much pro-Trump content as pro-Biden content on the app. 

TikTok success may not translate to votes, however. TikTok data shows that the #Biden2020 hashtag was used in 1.6 million posts, compared with 2.9 million posts that used the #Trump2020 hashtag.  

Trump’s social media presence has largely been on his own platform, Truth Social, where many prominent accounts are right-leaning, so his decision to join TikTok could help him reach a more mainstream audience on social media. 

But Trump could also use the platform to spread falsehoods, as he’s done on Truth Social. He has repeatedly denied the validity of the 2020 presidential election in his Truth Social posts, and blamed his “hush money” trial, which was prosecuted by the Manhattan district attorney, on the Biden administration. 

Kennedy, who has been known to amplify conspiracy theories on vaccines and COVID-19, has used TikTok to spread misinformation. 

The majority of Kennedy’s videos focus on his own pitch to voters and his role as an independent candidate. He repeatedly reminds viewers they don’t have to choose between “the lesser of two evils” in November and can vote for him instead. 

The Biden campaign’s approach to the platform has taken a different tone. The account has embraced viral audio clips and memes, and most videos highlight Trump’s missteps or policy plans. Of their more than 200 videos, 75% reference or depict Trump. Their second most-viewed video showed Trump at a rally in South Carolina, where he said, “These lights are so bright in my eyes that I can’t see too many people out there. I can only see the Black ones.” The video, captioned “… huh,” racked up 6.7 million views.

Trump had only posted one video as of Wednesday afternoon: a 13-second clip filmed from an Ultimate Fighting Championship announcing the launch of his account. 

“It’s my honor,” Trump said in the video, as UFC CEO Dana White announced his arrival on TikTok. The clip ends with Trump speaking to someone just off-camera, saying, “That was a good walk-on, right?”