As Newark woke up to a new mayor-elect on Wednesday, the groups that backed him declared his victory one for the “progressive” wing of the Democratic Party, saying it was part of a rising tide across the country of voters’ speaking out against charter schools and other incursions against labor unions and public education.

The election of the new mayor, Ras Baraka, was seen by many as a rebuke of Cory A. Booker, now a senator. In his nearly eight years as mayor, he attracted national attention to Newark, but alienated some who said he failed to work with political leaders or residents to improve the city’s troubled finances and schools.

Mr. Baraka, 44, is to be sworn in on July 1. Newark’s interim mayor, Luis A. Quintana, did not run in the nonpartisan election.

The new mayor will confront immediate problems: Newark has its highest murder rate in two decades; the state has threatened to take over the city’s troubled finances; and the school system, run by the state for two decades, has been beleaguered by criticism of the superintendent, who was handpicked by Gov. Chris Christie, a Republican.