Why is dissatisfaction so high? People have learned to take in stride Mr. Nagin’s tendency to shoot from the hip with a howitzer and have tended to draw some satisfaction from his ability to avoid the serious taint of corruption that has dogged many Louisiana politicians.

Now, however, that sense is coming to an end, after accusations arose in a civil lawsuit concerning city technology contracts. In a deposition, a former city official said he took a Hawaiian vacation with Mr. Nagin and their families in 2004 that was paid for by a company whose owner did extensive business with the city through other companies. Claims of other trips raising ethics questions were raised in later testimony.

At a news conference on April 7, the mayor defended the Hawaiian vacation. “I don’t see it as a violation of any law, any ethics rules,” he said, because he had been told that the city official  Greg Meffert, the former chief of technology for New Orleans  was paying for the trip, not the contractor.

“It’s been cleverly portrayed that there’s something wrong here, and no one has proven that yet,” Mr. Nagin said at the time. He acknowledged, however, that “there’s still a question whether this is illegal or unethical.” He declined requests for an interview.

Mr. Nagin has also been in a long stalemate with the City Council over budget issues and a struggle with news organizations over public-records requests for his e-mail messages. After a judge ordered the messages released, it emerged that thousands of messages had been deleted.

But the biggest issue is the state of the city. Dr. Renwick, of Loyola, said that despite positive signs of rebuilding in neighborhoods like the French Quarter and the Garden District, enormous areas of the city were still crippled and government services were balky at best.

Fixing a streetlight, Dr. Renwick said, can take months and repeated complaints. Over time, he said, “you build up a mass of people who are irritated.”