Twitter’s new owner, Elon Musk, threw his weight behind Republicans ahead of Tuesday’s midterm elections in the United States, saying they could use control of Congress to act as a balance against President Joe Biden’s Democrats.

The world’s richest person, Musk has faced criticism from some groups who believe his absolutist stance on free speech will increase misinformation on Twitter. Some advertisers have pulled spending from the platform, with Musk blaming critics concerned about content moderation.

His tweet to more than 110 million followers on Monday represented the first time the head of a major social media platform explicitly endorsed a US political party.

Musk, also CEO of Tesla, has been critical of the Biden administration and Democrats for their proposals to tax billionaires and give more tax incentives to union-made electric vehicles. Tesla does not have unions at its US factories.

He directed his Twitter message to what he called “independent-minded voters”, writing: “Shared power curbs the worst excesses of both parties, therefore I recommend voting for a Republican Congress, given that the presidency is Democratic.”

Later, he added, “I’m open to the idea of voting Democrat again in the future”, and said he had historically been an independent who had voted for Democrats.

Republicans are favoured to win a majority in the House of Representatives in Tuesday’s elections, with the Senate rated a toss-up by nonpartisan election forecasters. They could use a majority in either chamber to bring Biden’s legislative agenda to a halt and launch potentially politically damaging investigations into Biden’s administration and family.

Kyle Kondik, from the University of Virginia Center for Politics, said it was unlikely Musk’s words would influence the election’s outcome.

“It’s hard to expect any sort of celebrity ‘endorsement’, as this basically is, to have much if any effect on voter behaviour,” Kondik said.

The White House declined to comment on Musk’s tweet.

Musk, who frequently comments on US politics, previously said he would vote for Republicans but backs moderates of both major political parties.

He has said he was leaning towards supporting Florida’s Republican Governor Ron DeSantis for president in 2024 and that former President Donald Trump, who sources said is likely to launch another White House run in coming days, was too old to serve as president again.

Asked about Musk’s comments, White House Press Secretary Karine Jean-Pierre said: “The president has often spoken about the importance of voting, and I’m just going to leave it there as to not get involved in any kind of election conversation.”

Former Republican Speaker of the House Newt Gingrich described Musk’s comments as “very encouraging”.

New line for social media execs

Musk is not alone among social media executives in taking open political stances.

For instance, Sheryl Sandberg, former chief operating officer of Facebook owner Meta Platforms Inc, has donated heavily to progressive candidates and endorsed Democratic presidential contender Hillary Clinton in 2016.

Like other executives, however, Sandberg stopped short of explicitly telling her followers how to vote and took pains to keep a distance between her personal leanings and her management of the company’s platforms.

Former Twitter CEO Jack Dorsey has voiced a sense of alienation from both Republican and Democratic politics, while Meta CEO Mark Zuckerberg and his wife donated to two nonprofits that distributed grants to state and local governments to help them conduct elections.

Musk bought Twitter last month. In one of his first acts, the company laid off about half its employees and flagged a drop in advertisement revenue. But the company’s head of safety and integrity said the platform’s content moderation capabilities remained in place.

In a statement to the Reuters news agency, Jessica Gonzalez, co-CEO of Free Press, an advocacy group for media issues in democracy, said Musk’s comment showed he “is not showing himself to be an even-keeled CEO that advertisers can trust”.

Last year, Tesla, which counts California as its biggest US market, moved its headquarters from the Pacific coast state to the more conservative state of Texas. Musk also moved his personal residence from California to Texas, where there is no state income tax.

In April, Musk said on Twitter he believes that for the platform “to deserve public trust, it must be politically neutral, which effectively means upsetting the far right and the far left equally”.

Federal authorities are investigating Musk over his conduct in acquiring Twitter, the company said in a court filing last month. The US Securities and Exchange Commission and the Federal Trade Commission have not commented on any potential probes.