Going into the South Carolina primary election, former Vice President Joe Biden appeared to be a longshot to win the Democratic nomination for president. His comeback, while remarkable, was weeks in the making.

Now, even amid the COVID-19 crisis, Biden is leading substantially in the delegate count and has all but secured his position as the eventual nominee.

To learn more about the 2020 Democratic primary and the effect of COVID-19 on the race, download National Journal’s 2020 Election Toolbox and the 2020 Democratic primary delegate tracker.