It’s even possible — many Democrats say more likely than at any time in modern history — that the leading candidate will finish with a plurality but not a majority of delegates, leading to a brokered convention.

“It’s a real possibility, particularly if the field remains large until the end,” said Jaime Harrison, associate chair of the Democratic National Committee and a former chair of the South Carolina branch of the party. “The DNC officer in me is cringing, while the political junkie in me is fascinated.”

If several candidates run deep into the race, the competition for cash and delegates could turn brutal, according to Jeff Berman, who devised delegate strategies for Barack Obama in 2008 and Hillary Clinton in 2016 and helped rewrite the party’s nominating rules.