Yesterday, in the Missouri primary.

From the Missouri Secretary of State web site:

State of Missouri – Presidential Primary Election, March 10, 2020
Unofficial Results
as of 3/11/2020 6:24:20 AM
3653 of 3653 Precincts Reported
Office/Candidate Name Party Votes % of Votes U.S. President

Amy Klobuchar Democratic 2,652 0.402%
Tom Steyer Democratic 579 0.088%
Tulsi Gabbard Democratic 4,838 0.733%
Leonard J. Steinman II Democratic 176 0.027%
Cory Booker Democratic 647 0.098%

Joseph R. Biden Democratic 396,826 60.118%

Elizabeth Warren Democratic 8,066 1.222%
Pete Buttigieg Democratic 3,272 0.496%
Bernie Sanders Democratic 228,244 34.578%
Velma Steinman Democratic 190 0.029%
Henry Hewes Democratic 93 0.014%
Andrew Yang Democratic 944 0.143%
Roque De La Fuente Democratic 64 0.010%
John K. Delaney Democratic 158 0.024%
Julián Castro Democratic 103 0.016%
Deval Patrick Democratic 52 0.008%
Marianne Williamson Democratic 169 0.026%
Michael Bennet Democratic 203 0.031%
Michael R. Bloomberg Democratic 9,754 1.478%
Steve Burke Democratic 122 0.018%
Robby Wells Democratic 79 0.012%
William C. (Bill) Haas Democratic 391 0.059%
Uncommitted Democratic 2,461 0.373%

Party Total: 660,083

[emphasis added]

In Boone County:

Joseph R. Biden Democratic 15,283 50.494%
Bernie Sanders Democratic 13,604 44.947%

In Greene County:

Joseph R. Biden Democratic 15,490 51.630%
Bernie Sanders Democratic 13,288 44.290%

In Johnson County:

Joseph R. Biden Democratic 2,217 58.666%
Bernie Sanders Democratic 1,341 35.486%

In Kansas City:

Joseph R. Biden Democratic 31,434 57.680%
Bernie Sanders Democratic 20,912 38.373%

In Jackson County:

Joseph R. Biden Democratic 27,996 61.360%
Bernie Sanders Democratic 15,615 34.224%

In Clay County:

Joseph R. Biden Democratic 17,116 58.842%
Bernie Sanders Democratic 10,534 36.214%

In St. Louis City:

Joseph R. Biden Democratic 33,543 53.442%
Bernie Sanders Democratic 25,962 41.364%

In St. Louis County:

Joseph R. Biden Democratic 112,325 65.187%
Bernie Sanders Democratic 50,079 29.063%

Joe Biden (D) won every county in the state.