But Bush’s business record, enmeshed in international finance and some troubled former ventures in south Florida, could end up complicating his return to politics and his hopes to follow his father, George H.W. Bush, and his older brother, George W. Bush, into the Oval Office.

Last year, he took a step into the rarefied world of private equity and offshore investments, joining with former banking executives and a Chinese airline company to make bets on natural gas exploration and shipping. One of the funds was set up in the United Kingdom, a structure that allows the company to shield overseas investors from U.S. taxes.