NEW YORK — Billionaire executive Elon Musk, CEO of SpaceX and Tesla, said he thinks that $2 trillion could be eliminated from the federal budget after being introduced at former President Donald Trump’s Madison Square Garden rally.

Howard Lutnick, the chairman-CEO of Cantor Fitzgerald and chairman of the Trump 2024 Transition Team, introduced Mr. Musk as the soon-to-be-head of the new Department of Government Efficiency.

Mr. Lutnick, before he exited the stage, asked Mr. Musk how much could be “ripped out of this wasted $6.5 trillion House-Biden budget?”

Mr. Musk responded, “I think nearly $2 trillion. All that double spending is taxation, whether it’s direct taxation or indirect taxation, your money is being wasted,” he said. “And the Department of Government Efficiency is going to fix that.”

“We’re going to get the government out of your back pocket and pocketbook. America is just not done.  It is going to be great,” he said. “America is going to reach heights that it has never seen before.”

Mr. Musk implored Trump supporters to vote early, calling the election a “real election battle.”

“So, you need to get friends with family to vote, make sure they vote. Vote early. This is important,” he said. “We’re gonna be putting up a scorecard.”