Wet paper ballots caused scanners to fail at polling places in Manhattan and Brooklyn, which is leading to long lines for voters, Politico reported.
Media reports said the city's board of elections has sent out mechanics to fix problems with the machines.
Complaints about voting machine problems are coming in from all five boroughs of New York City.
Earlier on Tuesday, the weather caused problems for voters in a North Carolina county. That state's board of elections said humidity caused trouble with ballot scanners.
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