Former New York City Mayor Michael Bloomberg has the money and name recognition to shake up the Democratic presidential race, but he will face huge hurdles to the nomination if he makes the leap to become a formal candidate.

The billionaire media mogul is laying the groundwork for a possible candidacy and kept his options open by filing paperwork on Friday to run in the Democratic primary in Alabama, which has an early deadline for ballot qualification.

The decision to run would be an about-face for Bloomberg, 77, who announced in March that he would not seek the White House.