Here’s what to know about voting in today’s election. The Justice Department plans to monitor polling sites in five counties in California, a move that will likely heighten tensions on Election Day and in the days afterward during the vote-counting process.

High-profile races are unfolding across the country on Tuesday, including New York City's mayoral election and governor's races in New Jersey and Virginia. In California, voters will consider a ballot measure that puts forth a redrawn congressional map that could net Democrats five House seats.