As New York City grappled with the aftermath of Monday night’s mass shooting, the undertones of the mayoral election in November were on display.

Mayor Eric Adams tried to play the role of crisis manager as his chief opponent, Assemblyman Zohran Mamdani, moved quickly to return home from a vacation in Uganda.

The shooting, which claimed the lives of four victims, including a New York City police officer, was the first high-profile crisis to occur during the general election campaign.

The shooting may put concerns over gun violence back on voters’ minds, and may lead some to further scrutinize Mr. Mamdani, the Democratic nominee, who has relatively limited experience in government and has not handled a high-profile crisis while in office.

Mr. Mamdani, 33, a democratic socialist, embraced calls to “defund the police” in 2020 but no longer supports doing so. While some other mayoral candidates have called for hiring thousands of police officers, Mr. Mamdani has said that he would keep the police head count at its current level and create a new city agency focused on addressing mental health issues.

Mr. Mamdani was traveling back to New York City on Tuesday and planned to arrive by early Wednesday from Uganda, according to a person who was familiar with the matter. Mr. Mamdani had been celebrating his recent marriage at his family’s compound in Kampala.