The results come two weeks after voting in the primary ended, on June 22. While early returns showed Adams in the lead, tens of thousands of absentee ballots had to be counted and rounds of tabulations has to be done under the ranked-choice system in which voters ranked up to five candidates for mayor in order of preference. …
However, the new voting system was marred by an error made as votes were being counted on June 29, when elections officials inadvertently included 135,000 old test ballots in the count. The incorrect vote tallies were posted for several hours before officials acknowledged the error and took them down.
