The election process itself also already reflected Democratic wins: This was the first year that New Yorkers were allowed to vote early, after the newly Democrat-led State Legislature approved a bill allowing the practice in January. (Of registered voters, 1.9 percent cast their ballots early.)

At the same time, conservatives made their presence known. A Republican beat back a Democratic challenger in a district attorney race in Western New York, in which progressives, including a Democratic megadonor, had invested heavily. In New Jersey, a vulnerable Democratic state senator lost his seat to a Republican who is leading Mr. Trump’s New Jersey campaign.

Here are four things of note from Election Day 2019:

Ballot initiatives

New York City and Jersey City both left major decisions about the cities’ futures to voters.

New Yorkers overwhelmingly backed a system of ranked-choice voting, which allows voters to rank candidates in order of preference, rather than selecting only their top choice. The goal, supporters said, was to reduce runoff elections and minimize the risk of split votes: If no single candidate won a majority, the last-place finisher would be eliminated, and his or her votes would be redistributed to supporters’ second choices.

The system will be used only in primary and special elections and will apply to elections for mayor, comptroller, public advocate, borough president and the City Council. It will debut in 2021.

Though a group of elected officials mounted a last-minute opposition campaign, arguing that ranked-choice voting would leave minority candidates and voters at a disadvantage, the proposal passed with 73 percent support.