Octogenarian Biden begins new year facing age-old question on 2024 race

But if the answer is no, a vigorous battle to inherit his crown will ensue, with everyone from his vice-president, Kamala Harris, to his transportation secretary, Pete Buttigieg, expected to participate.

By all outward appearances, Biden currently plans to run for a second term.

Should he step down, any number of alternatives could emerge, from 2020 veterans like Buttigieg, Sanders and Harris to new contenders from the ranks of Democratic state governors, like Gavin Newsom of California, Gretchen Whitmer of Michigan, or Jared Polis of Colorado.