It's becoming increasingly clear that the fact that Bernie Sanders and Elizabeth Warren are viable contenders for the Democratic nomination for president is the primary motivation for billionaire Michael Bloomberg to get in the race. Bloomberg doesn't want any part of his billions going to paying a fair tax rate, to fully funding government and all the programs that will help people and rebuild federal institutions. He doesn't want to pay taxes. He wants to direct the millions he spends on fighting gun violence or climate change very publicly and to have his name plastered on every penny.
Because he's fundamentally a Republican. He got into the mayor's office in New York City with the endorsement of former Mayor Rudy Giuliani. And he has spent millions—millions—on Republican congressional campaigns, including hosting a fundraiser for Rep. Peter King in 2018 and donating to Rep. Dan Donovan, who was defeated. He also helped Republicans hold control of the New York state Senate. "The path to win the House ran through New York,” said Monica Klein, the Democratic challenger to King. "There were seven flippable seats in the state, and he supported Republicans in two of them. […] To come down and say he wants to be the head of the Democratic Party—the hubris is unbelievable.”
He endorsed and raised funds for former Sen. Scott Brown in his reelection bid against Elizabeth Warren in 2012. He gave $2,700 to Pennsylvania Sen. Pat Toomey and spent nearly $10 million on dark-money issue ads to keep him in office. In 2014, he gave $5,200 to Sen. Susan Collins in Maine. Protecting the status quo—and his low taxes—has been his priority, even at the same time that he's donated to Democrats. His bottom line seems to have been keeping the Senate, where his tax cuts are guaranteed, in Republican hands. Mike Mikus, former campaign manager for Toomey's 2016 Democratic opponent, Kathleen McGinty, pretty much nails it: "I'm certain his hand in giving Mitch McConnell a majority in the Senate will be remembered by a lot of Democratic voters."
When George W. Bush was president, Bloomberg gave donations to Bush, and only to other Republicans. He has never donated to Joe Biden, or Bernie Sanders, or Elizabeth Warren. It's hard to resist the notion that Bloomberg's political interests lie entirely in Michael Bloomberg, whether in preserving his wealth or in stroking his ego.