Obama calls Trump 'wannabe king' at Harris event

Election officials are increasingly confronting billionaire X owner Elon Musk on his own platform over election disinformation, but their reach typically pales in comparison to Musk's 200 million followers.

"It's just not a fair battle," said Larry Norden, a voting expert at the Brennan Center for Justice, a nonprofit think tank.

Henrico County registrar Mark Coakley, for example, received fewer than 100,000 views for a thread debunking a 2023 claim shared by Musk falsely alleging that "election integrity leaders in Virginia" found fraudulent votes in the county from the 2020 election.

The original post shared by Musk -- a vocal supporter of and donor to former President Donald Trump -- received 27.7 million views.

In Philadelphia, Musk reposted a tweet suggesting that 5,200 voters had registered with the same address. "This is crazy," Musk commented.

Seth Bluestein, a Philadelphia County Commissioner, replied hours later, tweeting, "The post you shared is spreading disinformation." But Bluestein's response garnered fewer than 10,000 compared with the nearly 10 million views for Musk's initial tweet.

-ABC News' Laura Romero and Lucien Bruggeman

Vice President Kamala Harris' rally near Atlanta, Georgia, on Thursday night -- her first with former President Barack Obama -- will feature more stars in addition to Bruce Springsteen.

The campaign announced that Spike Lee, Samuel L. Jackson, Tyler Perry and Mix Master David will also join the vice president at what is the first in a series of "When We Vote We Win" concerts.

-ABC News' Fritz Farrow, Gabriella Abdul-Hakim and Will McDuffie

Elon Musk's super PAC -- which had promised to give out a $1 million prize every day to a random swing state voter who signed its petition -- has yet to announce its fifth winner amid the Justice Department's questioning of the legality of the offer.

America PAC announced on Tuesday night its fourth recipient of a $1 million prize -- Andy Steinle of Holly Spring, North Carolina. The first three recipients were all Pennsylvania voters.

No winner was announced by the America PAC's website or social media pages on Wednesday.

A source familiar with the matter told ABC News Wednesday that the Justice Department had sent a letter to the America PAC warning that Musk's giveaway may violate federal law.

-ABC News' Soo Rin Kim

In a Wednesday social media post, former President Donald Trump suggested that Vice President Kamala Harris criticized him as a "fascist" because she is losing ground in the presidential race.

"She is a Threat to Democracy, and not fit to be President of the United States -- And her Polling so indicates!" Trump fired back at the vice president.

"Now she is increasingly raising her rhetoric, going so far as to call me Adolf Hitler," Trump added.

Trump did not mention why Hitler's name emerged. The New York Times reported this week that the former president allegedly praised Hitler, according to former White House chief of staff John Kelly.

-ABC News' Kelsey Walsh, Lalee Ibssa and Soo Rin Kim