Presumptive nominee and former vice president Joe Biden won with 56%, but lost a rather unusual number of votes and delegates in the penultimate primary to withdrawn candidates, senator Bernie Sanders and former mayor Michael Bloomberg.

The Puerto Rico Democratic primary had been originally scheduled for June 7, 2020,[2] but on August 2, 2019, then-governor Ricardo Rosselló signed a law that moved the date to the last Sunday in March, which would have been on March 29.

[3] Due to concerns amid the 2020 coronavirus pandemic, governor Wanda Vázquez first postponed the date to April 26, 2020,[4][5] signing the approvement on March 21.

[4] Later on April 2, the local Democratic party, as it was allowed to by the territory's new law, postponed the primary indefinitely until a new date would be chosen.

The 51 pledged delegates to the 2020 Democratic National Convention were allocated proportionally on the basis of the results of the primary.