Per that report, "Bush led a group that included former New York Yankees captain Derek Jeter, who may still explore a bid with other investors. The person confirming Bush's decision didn't give a reason, but said Bush and Jeter remain great friends."
Barry Jackson of the Miami Herald reported that Jeter's group will still pursue the purchase without Bush, with Jeter serving as the "control person."
Jackson offered more context on Tuesday's news:
Outside of Jeter's bidding group, Tagg Romney's ownership group is the most likely to win the bid. That group also includes former MLB pitcher Tom Glavine.
Romney is the son of former Republican presidential candidate and former Massachusetts Governor Mitt Romney.
According to the AP (h/t the Minneapolis Star Tribune), "Bush's group and the Romney group had bid about $1.3 billion to buy the team from Jeffrey Loria, who bought the Marlins for $158.5 million in 2002 from John Henry."
Jackson reported in early March that Loria was expected to sell the team this year.