In late 2024, FBI investigators had enough evidence to launch a sweeping bribery probe that could ensnare top lawmakers, including Sen. Susan Collins. The agency was examining interactions between Collins and a top donor: Martin Kao, CEO of defense contractor Navatek.

According to Kao, in 2019, the head of the pro-Collins super PAC met with him and other Navatek execs and asked for a $500,000 donation. Government contractors are banned from making political contributions. For the company to offer donations to Collins in exchange for an official action, or for Collins to accept, would constitute criminal bribery.

To skirt campaign finance laws and conceal the source of the funds, Kao sent an initial $150,000 to the super PAC using a shell company, saying he had cleared it with his lawyer. The head of the super PAC knew Kao........

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