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.Musk drew praise from conservatives at his rallies while fielding questions about artificial intelligence,

Elon Musk is offering $100 to registered voters in Pennsylvania to sign a pro-Donald Trump petition "in support of free speech" and the "right to bear arms."

Musk, the richest man in the world with a net worth of $242 billion, according to Forbes, has pledged to give away $1 million a day to voters for signing his political action committee's petition backing the Constitution, a pledge experts say raises legal questions.