Still, the city’s public schools remain under state control, with all but a handful classified as failing. Residents pay premium taxes, even as garbage cans overflow and potholes go unrepaired. Though downtown neighborhoods have gotten safer, neighborhoods farther out still struggle with high crime rates. Many have long suspected that the city’s recent success was due to its proximity to New York, and not because of, but in spite of, the city’s political establishment. Hudson County residents have reason to temper their optimism: the fresh-faced new mayor of Hoboken, Peter Cammarano, was one of 44 officials swept up in the bribery scandal that brought down Jersey City’s deputy mayor four years ago.

The second of three sons born to immigrants from Israel and Romania who own a deli in Newark, Mr. Fulop grew up in Edison, N.J., and like so many of his new constituents, moved here to work for Goldman. He bought an apartment near the waterfront in 2000, figuring the influx of financial firms would make the city a good investment.

After his tour in Iraq, he ran unsuccessfully for Congress before narrowly winning a seat on the City Council in 2005. Four years ago, Mr. Fulop expanded his political influence by sponsoring a winning slate of school board members. More recently, he helped bring in a longtime veteran of the New York City schools, Marcia Lyles, as superintendent.

And he has hammered city officials about ethics violations since 2009, when the sweeping corruption investigation known as Operation Bid Rig ensnared several dozen Hudson County politicians, including several associates of Mayor Jerramiah T. Healy, on charges of accepting bribes from a developer.

Image Steven Fulop, a former trader at Goldman Sachs. Credit... Nadav Neuhaus for The New York Times

“I don’t think people realize how much that left an impression on the city,” said Shelley Skinner, who met Mr. Fulop after he responded to an e-mail complaining about the quality of the schools, encouraging her and a group of parents to organize. “O.K., Hudson County is corrupt, but this is what our tax dollars are going toward? People with kids think, ‘I’m not getting a quality school because of this?’ ”

“After his election, so many of my friends said, ‘We can stay,’ ” she said.

The election was nonpartisan, expensive and rollicking. Mr. Healy and Mr. Fulop together spent about $2 million.