The barrage of spending comes as Republicans fight to overcome Trump’s declining popularity and cost of living concerns.

Elon Musk, the trillionaire tech mogul and backer of far-right causes, has reportedly spent $366m since last year to buoy the Republican Party in the United States midterm elections.

The New York Times first reported on Monday that Musk has spent $276m since July alone, including $158m for a super PAC focused on Republican Senate candidates, making him the largest single donor this year.

Musk is considered a close ally of President Donald Trump, the leader of the Republican Party, and was a special government adviser to the White House last year.

Musk’s political action committee, America PAC, has confirmed the spending totals. In a statement to The New York Times, a spokesperson framed the record amount as necessary to defend Congress from a Democratic takeover during the midterm races.

“These robust investments have allowed the GOP apparatus to get its message out so Republicans can have a fighting chance to defy history,” America PAC spokesman Andrew Romeo told the Times.

The barrage of spending by Musk comes as Republican candidates are fighting to overcome Trump’s low popularity and rising concerns about the cost of living among US voters.

Democrats are hoping to capitalise on voter dissatisfaction with Trump’s tenure to seize control of Congress, where Republicans currently hold majorities in both the House of Representatives and the Senate.

The influence of wealthy donors and PACs has long been the subject of criticism. Opponents argue that such spending distorts US politics in favour of powerful interests.

Musk became the world’s first trillionaire in June, when his aerospace company SpaceX made its initial public offering (IPO) on the Nasdaq stock exchange.

The tech entrepreneur had previously said that he planned to step back from his involvement in US politics, stating in May that he had “done enough” and did not have plans for large spending efforts.

Still, Musk has leveraged his tech holdings and wealth to support right-wing groups around the world.

Last year, for instance, politicians in Germany accused Musk of trying to meddle in the national election. Musk has been a vocal backer of the Alternative for Germany (AfD) party, which has been accused of adopting a discriminatory stance on immigration and other issues.

Voters in the US will head to the polls on November 3 to cast their ballots in the midterms, which will decide key state and local races, as well as congressional majorities.

The Republican Party is considered to have a sizeable financial advantage over the Democrats ahead of the race, with heavy spending from groups such as MAGA Inc, a pro-Trump super PAC named for the president’s “Make America Great Again” movement.

As of August, MAGA Inc reportedly had $416m in its coffers. The tracking site AdImpact found that it had spent $22m over the past month alone on the tight race unfolding for the open Senate seat in Texas.

Trump has also increased his campaign activities, hosting a string of rallies in the final weeks before the election to help Republicans push their message.

But Democrats appear confident that the Republicans’ spending advantage will not be enough to counter the effects of growing dissatisfaction with Trump.

“Republicans are hoping to buy these elections, injecting tens of millions into races to try and outrun their unpopular candidates, unpopular president and unpopular economy,” said Lauren French, a spokesperson for Democrats’ Senate Majority PAC.