For four days billionaire Elon Musk toured Pennsylvania, putting his money and fame into helping Republican Donald Trump's campaign to take back the White House in November.

A look at the legal ins and outs of a Trump-ally scheme that some legal experts call illegal — but which at the very least exploits a loophole.

Elon Musk’s $1 million giveaway for voters who sign his free-speech and gun-rights petition falls into a gray area of election law, and legal experts are divided about whether the billionaire supporter of Donald Trump could be running afoul of prohibitions on paying people to register to vote.