After Trump introduced Musk to the stage, the tech mogul enthusiastically jumped in the air several times while supporters cheered. Musk, who wore a black Make America Great Again cap, warned in his speech that "this will be the last election" if the former president does not win in November while urging people to vote.

Shares of Trump Media & Technology Group Corp. continued their rally Tuesday, gaining 18% in afternoon trading after ending Monday’s session up 11.5%. The stock has been rallying following an appearance by Tesla Inc.

Elon Musk has praised Donald Trump as the only candidate “to preserve democracy in America." The SpaceX and Tesla CEO stood alongside the GOP nominee at a rally Saturday in Butler, Pennsylvania, where Trump had survived an assassination attempt in July.