At Oklahoma senator Markwayne Mullin’s swearing in as Homeland Security secretary, Donald Trump did what he tends to do at ceremonies: wandered. He bragged about his own margins in the Sooner State, complimented one of Mullin’s sons on his “good genetics,” then returned to the point — Mullin, Trump said, had succeeded in business because “everything he’s touched, he turns to gold.”

The line is on-brand for Trump, who was right about Mullin’s business prowess. Before entering politics, Mullin and his wife Christie turned his family’s struggling plumbing business into a statewide home services empire. He was a multimillionaire when he first won a House seat in 2012. His net worth climbed again after he sold a majority stake to a private equity firm in late 2021, then reinvested the proceeds across real estate and a sizable portfolio of stocks and other assets. Today, Forbes estimates that he is worth around $60 million—12 times the fortune of his predecessor, Kristi Noem.

That figure isn’t airtight. Federal officials disclose their assets in ranges, not exact figures, making true precision impossible. Mullin’s borrowing also complicates the picture. In 2024, he opened a line of credit at 6.1% interest whose size is somewhere between $5 million and $25 million. He also discloses five additional loans taken out in the last three years. Four are from Arvest Bank, owned by the billionaire Walton family, whom he apparently owes between $3.5 million and $16 million at 6.75% interest, according to his most recent disclosure. Robson and Jim Walton both gave to Mullin’s Senate campaign in the last two years.

Forbes dug into public records to narrow down his real estate holdings, modeled how much he may have made in selling Mullin Plumbing and examined years of financial disclosures to arrive at our $60 million figure. A DHS spokesperson declined to answer specific questions about Mullin’s net worth, sale of his business and debts, instead sending a statement describing........

© Forbes