A Democrat with a long political history in Pennsylvania and a tough-on-crime platform, Cherelle Parker, defeated a rival backed by her party’s left wing and won Philadelphia’s mayoral primary on Tuesday, likely setting her up as the city’s 100th mayor and the first woman to serve in the role.

Ms. Parker, 50, who served for 10 years as a state representative for northwest Philadelphia before her election to the city council in 2015, asserted herself as a leader whose government experience would allow her to address gaping problems with public safety and quality of life in the nation’s sixth-largest city.

In contrast with “Defund the Police” mantra popular among the left wing of Ms. Parker’s party, she advocated for a crime crackdown, vowing to add 300 more police officers as part of a community policing proposal, the Philadelphia Inquirer reported. She also called for restoring the policing tactic known as Stop, Question, and Frisk, the Inquirer reported, and portrayed herself as an advocate for the city’s middle-class neighborhoods.

The win was a disappointment to liberals who rallied around Helen Gym, who was backed by Senator Sanders and Congresswoman Alexandria Ocasio-Cortez.

With just more than 86 percent of ballots counted, Ms. Parker was far ahead with 28.5 percent of the vote, the Inquirer reported, compared with 18.4 percent for Ms. Gym. Ms. Parker will go up against Republican David Oh in the November 7 general election.

Ms. Parker emerged from a crowded field of five front-runner Democratic candidates vying to replace Democrat Jim Kenney, who is term-limited. 

She beat out other former city council members who resigned from their seats to throw their hats in the ring; a state representative; a former city controller; and a political outsider businessman.

The Philadelphia race serves as the latest barometer of how residents of some of the nation’s largest cities hope to emerge from the pandemic, which heightened concerns about crime, poverty and inequality. 

The results have sometimes been tumultuous in other parts of the country, leading to the defeat of the incumbent mayor of Chicago in February and the ouster of San Francisco’s district attorney last year.

Ms. Parker pledged to “stop the sense of lawlessness that is plaguing our city” by putting hundreds more officers on the street to engage in community policing. Ms. Parker pushed for officers to use every legal tool, including stopping someone when they have “just cause and reasonable suspicion.”

She received support from members of the Philadelphia delegation in the House, as well as members of Congress. She was also backed by labor unions and a number of wards in the city, and Mr. Kenney said he had cast his ballot for her.