While Biden is still far away from the magic number to clinch the Democratic Party nomination, his wins last night made it that much more difficult for Sanders to catch him.
With his own campaign event in Cleveland also canceled because of the Coronavirus, Sanders went back to his home town of Burlington, Vermont, as he did a week ago on Super Tuesday.
But unlike Super Tuesday, Sanders made no statement to cameras or reporters, a highly unusual move during a presidential primary race.
"Tonight's a tough night," Rep. Alexandria Ocasio-Cortez (D-NY) acknowledged in a live chat on Instagram as the votes came in.
Some of his top supporters vowed to press on.
Next up are four important states for November - Arizona, Illinois, Ohio, and Florida, as 577 delegates are at stake next week, with a debate planned for Sunday night in Phoenix between Biden and Sanders.