Michael R. Bloomberg will file paperwork on Friday afternoon to place himself on the Democratic presidential primary ballot in Alabama, advisers said, a first step toward competing for the party’s nomination to challenge President Trump next year.
Advisers to Mr. Bloomberg said that he had not made a final decision about whether to run for president, and that he planned to enter the Alabama primary as a preliminary step because
The news of his revived interest in the race drew scorn from several leading Democrats, including Ms. Warren and Mr. Sanders, who branded him a billionaire seeking to buy the presidency to protect his own interests.
A political nomad with respect to party affiliation, Mr. Bloomberg was elected mayor three times on the Republican ticket before he registered as a Democrat during the midterm elections and spent more than $100 million to help the party take control of the House of Representatives.
He holds liberal views on a range of important issues — including gun control, climate change, immigration and abortion rights — but he is more conservative on issues related to the economy and law enforcement, and his record in government and business is ripe for intensive scrutiny.