“WE ARE brick city. We are like bricks themselves. We are strong. We are resilient. We are enduring.” So said Cory Booker, mayor of Newark, New Jersey, in his state-of-the-city address this year. It is highly likely that Newark will soon have to endure without him. On August 13th Mr Booker handily won the Democratic primary in the special election to fill an empty Senate seat. In a low turnout, he got 59% of the votes cast. Once synonymous with urban decay, Newark is now synonymous with Mr Booker. He was elected mayor in 2006 with a mandate to revitalise the city. To do so, his first battle was to get crime rates down. He hauled the police department into the 21st century by installing computers in precincts and putting cameras and gun-detection technology on to the streets. Though there are still many parts you should not visit after dark, since 2006 the city has seen a 27% decline in shootings and a 17% decline in murders.

The mayor’s already glossy reputation was enhanced by various exploits. He once chased down a suspected robber. He took hurricane victims into his home. He rescued a neighbour from a fire, and lived on food stamps for a week. Now, using Twitter (on which he has 1.4m followers), he responds quickly to any problem, from fixing a street light to rescuing a dog.

Thanks to him, jobs and investment have poured into the city. Much of the money has come from the mayor’s large network of friends, who include hedge-fund managers as well as Oprah Winfrey. Mark Zuckerberg, the founder of Facebook, was persuaded by Mr Booker to donate $100m to help improve the city’s schools, which are under state control. “He drew attention to Newark on a scale that we’ve never seen in Newark history,” says Clement Price of Rutgers University. What happens when he goes?

His three would-be successors have big shoes to fill. Ras Baraka, a city councilman who has long opposed Mr Booker, is close to political royalty in Newark. His family has been in the city for over 70 years and he is the son of a well-known (and controversial) poet and activist. Less respectably, he is backed by Sharpe James, the previous mayor, who went to prison for corruption.

Shavar Jeffries, a former assistant attorney general, has an all-too common Newark story: he was brought up by his grandmother when his mother was murdered. Anibal Ramos, if elected, would be the first Latino mayor in New Jersey’s largest city; he reflects a growing “brown Newark”. Mr Ramos is the only candidate who has said he will build on what Mr Booker has done.

And there is much to do. Many shops are still shuttered. Crime is still too high. Unemployment is in double digits. Poverty is pervasive; one child in three is poor. Some Newarkers cannot wait for Mr Booker to go. “Downtown looks great,” gripes one, “but he is not doing enough for the rest of the city.” Ben Dworkin, of the Rebovich Institute for New Jersey Politics, puts this in perspective: Newark’s problems “were not created overnight and will not be solved overnight”.

City Hall is working to ensure the long-term survival of successful policies, such as a re-entry programme for ex-convicts, which has helped lower rates of re-offending. More than 1,700 ex-convicts return to Newark from state prison annually, and another 1,400 are released from the local jail every month. The city uses taxes from car rentals to pay for the programme.

At present, a third of all construction in the state is happening in Newark. Around $1 billion was ploughed into development in 2011-12; some $2 billion-worth of projects are in the pipeline. Panasonic has moved its North American headquarters to Newark. Biotrial, a French drug company, is building its North American headquarters there. Prudential’s new $450m office tower is about to rise on Broad Street, the main avenue. Although most expect a dip in the city’s visibility, Christian Benedetto of HSB Advisors, a property broker, says “Mr Booker put Newark on the map. That’s not going away.”