WASHINGTON (Reuters) - Elon Musk spent over a quarter of a billion dollars to help Donald Trump win November's presidential election, according to new filings, underscoring the influence one of the world's wealthiest people had on this year's White House race.

The billionaire owner of electric car maker Tesla and SpaceX gave $259 million to groups supporting Trump's 2024 campaign, according to new Federal Election Commission filings released late on Thursday.

The huge donations made Musk one of the biggest underwriters of a presidential campaign in U.S. history, helping him to become a powerful political ally of Trump and someone who now plays a key role in shaping the incoming Republican administration's policy agenda.

Musk gave $239 million to America PAC, a super PAC he founded to help turn out voters for Trump.

In late October Musk gave an additional $20 million to RBG PAC, a group that sought to convince voters that Trump would not sign into a law a national abortion ban, according to the FEC filings. The group's name refers to the late Supreme Court Justice Ruth Bader Ginsburg, a liberal icon known for her support of abortion rights.

Musk, who also owns the social media platform X, has emerged as a close advisor in Trump's transition team. Trump has chosen him, along with former Republican presidential candidate and entrepreneur Vivek Ramaswamy, to head a task force aimed at slashing government spending and regulations.

Musk and Ramaswamy met on Capitol Hill on Thursday with lawmakers whose support they will need to win the sweeping spending cuts Trump has asked them to find.

The two men have called for firing thousands of federal workers, slashing regulations and eliminating programs whose authorization has expired, such as veterans' healthcare.

Musk has also been a regular fixture and Trump confidante at the president-elect's Mar-a-Lago Florida estate during the transition.