The challengers in the Democratic primary to represent the Fifth City Council District have not made a convincing case for tossing out the incumbent.

That's because there's not much of a case to make.

The Inquirer endorses DARRELL CLARKE for reelection. Clarke, 54, has been a thoughtful voice on crime, recreation and education since 1999. He deserves another term representing parts of Center City and North Philadelphia.

Clarke has been a prime catalyst for the substantial growth in affordable housing units in struggling parts of his district.

Although he represents one district, Clarke's work has benefited city residents in other neighborhoods.

He chaired a task force that is credited with helping to lower auto insurance rates by an average of 20 percent. He is a leading proponent of the city's using police surveillance cameras to combat crime. And he has been at the forefront of legislation to take illegal guns off the street, although this effort has been stymied by the gun lobby and its allies in Harrisburg.

Clarke also has promoted a sensible plan to transform the governance of Fairmount Park by changing the city charter. If it comes to pass, the measure should free up more money for park maintenance.

A lesser incumbent might fear the high-quality opponents that Clarke has.

Haile Johnston, 34, of Strawberry Mansion, was employed most recently in the city's public health division. He co-founded a nonprofit group to revitalize neighborhoods, and has been active in community development groups and the city's Mural Arts Program. Johnston says the city needs to invest in more youth programs, and foster more town-watch activities instead of installing "dehumanizing" surveillance cameras.

John Longacre, of Fairmount, owns a real-estate management company and a pub. He is a founding member of the Francisville Neighborhood Development Corporation. Longacre says the city needs many more surveillance cameras to fight crime. He's a supporter of the city's tax-abatement program, and he'd re-establish a city office to attract more businesses to Philadelphia. He criticizes Clarke for ineffective constituent service.

Perhaps the most valid criticism of Clarke is that he has been too reliable a vote for Mayor Street. With a new mayor next year, Clarke should emerge from his mentor's shadow and exert even more leadership on Council.