SpaceX and Tesla founder Elon Musk speaks at a town hall with Republican candidate U.S. Senate Dave McCormick at the Roxain Theater, Oct. 20, in Pittsburgh, Pa. Musk also awarded an attendee $1 million dollars during the event. Musk has donated more than $75 million to America PAC, which he co-founded with fellow Silicon Valley venture capitalists and tech businessmen to support Republican presidential nominee, former U.S. President Donald Trump. AFP-Yonhap

Pennsylvania's Democratic governor, Josh Shapiro, on Sunday called on law enforcement to investigate billionaire Elon Musk for his promise at a weekend pro-Trump rally to give away $1 million each day until Election Day.

Musk on Saturday gave a $1 million check to an attendee at the rally in Harrisburg, Pennsylvania, which was hosted by America PAC, a political action group the Tesla CEO set up to back Republican Donald Trump in the Nov. 5 presidential election.

Shapiro said on NBC's "Meet the Press" that Musk's plan to give money to registered voters in Pennsylvania is "deeply concerning" and "it's something that law enforcement could take a look at."

The money is the latest example of Musk using his extraordinary wealth to influence the tightly contested presidential race between Trump and his Democratic rival Vice President Kamala Harris. Pennsylvania is a must-win state for both Trump and Harris. Musk's America PAC is playing a major role in helping mobilize and register voters in battleground states that could decide the election, but there are signs it is having trouble meeting its goals, Reuters was first to report on Friday.

The lucky recipient of Saturday's check was a man named John Dreher, event staff said.

"By the way, John had no idea. So anyway, you're welcome," Musk said as he handed Dreher the check.

On Sunday, Musk handed a second $1 million check to a woman at an event in Pittsburgh, according to a post by America PAC on X.

Musk is promising to give $1 million each day to someone who signs his online petition, which reads: "The First and Second Amendments guarantee freedom of speech and the right to bear arms. By signing below, I am pledging my support for the First and Second Amendments."

To be eligible for the $1 million, petition signers must be a registered voter and live in one of the seven swing states: Arizona, Georgia, Michigan, Nevada, North Carolina, Pennsylvania and Wisconsin, according to the America PAC website.

The petition also offers $100 to each registered Pennsylvania voter who signs and $100 for referring a registered Pennsylvania voter to sign.

The legality of the giveaways is sure to come under scrutiny in the coming days.

It is a federal crime to pay people with the intention of inducing or rewarding them to cast a vote or to get registered, an offense punishable by prison time. The prohibition covers not only monetary expenditures, but also anything of monetary value like liquor or lottery chances, a Justice Department election-crimes manual says.

The Harrisburg event was the third in as many days in Pennsylvania, where Musk is painting November's election in stark terms and encouraging supporters to vote early and get others to do the same. Attendees of Saturday's event had to sign the petition, which allows America PAC to garner contact details for more potential voters that it can work to get to the polls for Trump.

Musk, ranked by Forbes as the world's richest person, so far has supplied at least $75 million to America PAC, according to federal disclosures, making the group a crucial part of Trump's bid to regain the White House.

The entrepreneur has increasingly supported Republican causes and this year became an outspoken Trump supporter.

Trump in turn has said if elected he would appoint Musk to head a government efficiency commission. (Reuters)