In the weeks since Zohran Mamdani decisively won the Democratic primary for mayor of New York City, many elected officials and prominent unions have become converts, embracing his viral messaging about making the city more affordable.

But some leaders, like Representative Hakeem Jeffries, the Democratic House minority leader, have been more cautious, praising Mr. Mamdani but still needing some persuasion.

On Friday, Mr. Mamdani began making inroads on his persuasion tour, meeting for an hour with Mr. Jeffries in his Brooklyn congressional district in East New York in an effort to get to know him better.

There was no endorsement announcement after the meeting, but both leaders spoke positively afterward.

The meeting was “constructive, candid and community-centered, with a particular focus on affordability,” said Justin Chermol, a spokesman for Mr. Jeffries.

The men discussed public safety, antisemitism, gentrification and efforts by Democrats to take back control of the House next year, and they “agreed to reconvene shortly” with other leaders, including other members of the New York City congressional delegation, Mr. Chermol said.