COUNCIL BLUFFS, Iowa — Pete Buttigieg scored a come-from-behind victory in Council Bluffs’s 18th Precinct by picking up nine votes from minor candidates in the second ballot. But Bernie Sanders’s top supporters in the precinct left upset, claiming their two-vote loss was due to a miscount.

Some voters started the evening unaligned, some voters realigned before the realignment period, and others realigned to nonviable candidates. According to Sanders’s acting precinct captain, some Sanders voters left early, and yet the precinct chairwoman conducted the count primarily by counting heads, using the paper ballots only as a backup.