A businessman making his first run for office coasted to victory over a popular police chief in Saturday's runoff for mayor of Louisiana's largest city.

Complete but unofficial results gave Cox Communications vice president Ray Nagin 76,469 votes, or 59 percent, to 53,781 or 41 percent for New Orleans Police Superintendent Richard Pennington. It may be a week or two before results become official.

Nagin, who will replace two-term Mayor Marc Morial, asked supporters to have patience as he works to change the city.

"I don't have a Superman undershirt under my suit," he told supporters who packed a hotel ballroom. "It didn't take us one year to get into this shape, and it won't take a year to get out. I predict a tough 18 months," he said.

Pennington, whose contract ends in early May, returns to work Sunday as police chief. He was relaxed and smiling as he conceded to Nagin, saying he will work with the new mayor's transition.

He said he has not considered either any other job offer or whether he would remain police chief if Nagin wants him to.

"The new mayor has an opportunity to select a new chief. I have to leave that up to him," Pennington said. "I'm not going to lobby for anything personally."

Nagin said he won't consider whether to replace him until the transition period is over.

"He is police chief until May or so, and we're going to honor him as such," he said.

Both candidates are political newcomers who took leave from their jobs to campaign after voters turned down Morial's attempt to change term limits.

It has been 66 years since New Orleans' had a mayor who had never before held elected office.

Nagin, 45, was the surprise leader among 15 candidates in last month's general election, but he held a commanding lead through public opinion polls going into Saturday's runoff.

Pennington, 54, last month's second-place finisher, campaigned hard and hoped for an upset.

Morial, who hired Pennington away from the Washington, D.C., police force, did not endorse anyone in either primary or runoff.

Nagin came to a foundering cable franchise as controller of its accounting system in 1985, and has turned it into one of Cox's top franchises. Pennington was credited with cleaning up a corrupt department and slashing the city's crime rate since arriving in 1994.

Both candidates are black Democrats in a majority black city but endorsements from two of the black candidates he defeated last month helped Nagin among black voters. He carried much of the white vote in the last election and polled well among upper- and middle-class blacks.

The last person who became mayor without being elected to any other office was Robert Maestri, who didn't even have to run.

He replaced T. Semmes Walmsley, who had resigned in 1936 after a political struggle between the Huey Long machine and the city's Old Regular organization.

Maestri, a businessman and state conservation commissioner, was Long's choice but was acceptable to both sides. Nobody ran against him, so under state law he was automatically elected.