Elon Musk’s $1 million daily donation to voters in battleground states may be about to be shut down in Pennsylvania.

Democratic Philadelphia District Attorney Larry Krasner filed a lawsuit Monday to stop what he described as an “illegal” lottery run by Musk’s America PAC, which he launched in May to supporting former President Donald Trump’s campaign.

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“The Philadelphia District Attorney is charged with protecting the public from public nuisances and unfair business practices, including illegal lotteries,” Krasner said. in a statement. “The DA is also responsible for protecting the public from interference with the integrity of elections.”

“Today, the Philadelphia District Attorney filed a civil lawsuit under Pennsylvania law,” Krasner continued. “This civil action does not preclude or require possible future actions under Pennsylvania criminal law. The Philadelphia District Attorney will litigate the factual allegations and legal arguments underlying today’s filing in the file and before the court.”

Musk’s contest offered a daily prize of $1 million to registered voters in swing states who sign his political action committee’s petition supporting the First and Second Amendments to the U.S. Constitution.

But is the draw legal?

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Brendan Fischer, a campaign finance expert and deputy executive director of the investigative watchdog group Documented, explained why he thinks the lottery might be breaking the law.

“The problem is not that Elon Musk is encouraging people to sign up, which is a good thing,” Fischer said. “But he is potentially paying people to register or conditioning payments; he is conditioning those payments on their registration and that appears to violate the law.”

Several checks have already been offered to the winners, including Kristine Fishell, who praised Musk for the “wealth and responsibility” he uses to “save speech.”

“This could represent the next frontier of money and politics,” she added, “where billionaires give money directly to voters in exchange for their registration and potentially their vote.”