Elon Musk makes appearance at Trump rally in Butler, Pa.

Billionaire tech executive Elon Musk cast the upcoming presidential election in dire terms during an appearance with Donald Trump, calling the Republican presidential nominee the only candidate “to preserve democracy in America.”

The CEO of SpaceX and Tesla who also purchased X, Musk joined Trump in Butler, Pennsylvania, on Saturday at the site where the former president survived an assassination attempt in July. Musk said “this will be the last election” if Trump doesn’t win. Wearing a cap with the “Make America Great Again” slogan of Trump’s campaign, Musk appeared to acknowledge the foreboding nature of his remarks.

“As you can see I am not just MAGA — I am Dark MAGA,” he said.

It was the first time that Musk joined one of Trump’s rallies and was evidence of their growing alliance in the final stretch of the presidential election. Musk created a super political action committee supporting the Republican nominee and it has been spending heavily on get-out-the-vote efforts. Trump has said he would tap Musk to lead a government efficiency commission if he regains the White House.

Trump joined Musk in August for a rare public conversation on X, a friendly chat that spanned more than two hours. In it, the former president largely focused on the July assassination attempt, illegal immigration and his plans to cut government regulations.

Before a large crowd Saturday, Musk sought to portray Trump as a champion of free speech, arguing that Democrats want “to take away your freedom of speech, they want to take away your right to bear arms, they want to take away your right to vote, effectively.” Musk went on to criticize a California effort to ban voter ID requirements.

The event took place at the same property where a gunman’s bullets grazed Trump’s right ear and killed a Trump supporter, Corey Comperatore. The shooting left multiple others injured.

Several members of Comperatore’s family, as well as other attendees and first responders from the July rally, returned to the site on Saturday. Also appearing with the former president were his running mate Republican Ohio Sen. JD Vance, son Eric Trump, daughter-in-law and RNC co-chair Lara Trump, along with Pennsylvania lawmakers and sheriffs.