Josh Kraft, the longtime nonprofit leader and younger son of billionaire New England Patriots owner Robert Kraft, has filed paperwork with state campaign finance regulators to run for mayor of Boston as a Democrat.

The philanthropist and son of billionaire Patriots owner Robert Kraft is preparing to challenge Boston Mayor Michelle Wu.

Josh Kraft, son of the billionaire New England Patriots owner and head of the family’s philanthropic arm, is planning to announce a run for mayor of Boston, according to two sources close to