Unofficial returns showed Mike Duggan defeating Wayne County Sheriff Benny Napoleon 55 per cent to 45 per cent. Napoleon conceded defeat late Tuesday in a race where Duggan outspent him by about 3-to-1 heading into Tuesday's election.
"It's been an amazing year," Duggan told his supporters during a victory celebration when all precincts reported late Tuesday night.
"Thank you, Detroit," he added. "We ran a campaign against an opponent who gave us a very strong race. Now the real work begins."
Napoleon congratulated Duggan in his concession speech.
"The people have spoken," Napoleon said. "I'm going to keep fighting for Detroit and fighting for the people. This is not over."
When he takes office in January, Duggan will be Detroit's fourth mayor since 2008. He will succeed Mayor Dave Bing who declined to seek re-election following one term in office.
This election has been shadowed by the presence of turnaround specialist Kevyn Orr, who was hired in March by the state to fix Detroit's finances. In July, Orr made Detroit the largest U.S. city to file for bankruptcy.
Both Duggan and Napoleon said during the campaign that Orr should leave the city and allow the new mayor to fix Detroit's finances.
"I'm going to try to shorten Kevyn Orr's stay," Duggan told The Associated Press heading into the election.
But the reality is that Duggan will have little power under Orr, who has complete control of how Detroit pays its bills and spends its money.
Duggan, an ex-county prosecutor and former chief of the Detroit Medical Center, had said he wanted to convince Orr's boss, Gov. Rick Snyder, to allow him to develop a team and a plan to resuscitate the city's fiscal condition if elected mayor.
"I think the state will be willing to turn it over quicker if they see a strong mayor in there," said Michael Twomey, who voted for Duggan.
"You want someone in there who has experience on a major level," said the 67-year-old retired truck driver who lives on Detroit's northwest side. "I just want to see somebody in there with not just good intentions — somebody who can really do something; somebody who is willing to do something. A strong mayor in other words. I don't feel the city's had a strong mayor in a long time."
Both Duggan and Napoleon campaigned on fixing Detroit's deteriorating neighbourhoods and reducing the high crime rate in a city that struggles to respond to 911 calls on time. Detroit has more than 30,000 vacant houses and buildings. Bing's administration has demolished about 10,000 empty and dangerous houses during his four-year term.
But anything the new mayor wants done that requires money must first get Orr's approval. Orr said in congratulatory statement Tuesday night that his office will meet with Duggan to discuss collaboration on the city's turnaround.
"In this time of important change for the City, Detroiters have come together to voice their desire for progress," Orr said. "I look forward to working with Mayor-elect Mike Duggan to build the vibrant and strong future the citizens of Detroit deserve."
Snyder did not endorse a candidate, but after testimony last week in bankruptcy court, he held firm in his decision to appoint Orr and keep him in place until Detroit emerges from bankruptcy and its finances are fixed.
"I look forward to working with him on making Detroit a safe and attractive place for people to live, work, invest, and do business," Snyder said of Duggan in a statement. "Mayor-elect Duggan's financial acumen and experience in turning around the Detroit Medical Center and other entities should serve him well in his new role.
"These are challenging times for our state's largest city as we resolve problems that have been decades in the making. But I know that brighter days are ahead and Detroit's turnaround is already underway," the governor said.
Detroit's mayor cannot remove Orr. Under state law, that only can be done by the governor or an act of the state Legislature. However, once Orr's 18-month contract ends, a supermajority vote by the City Council and mayor can choose not to renew it.
Bing has always been opposed to Detroit having an emergency manager and has been frustrated by the relationship he has with Orr, saying that Orr hasn't communicated well with the mayor's office.
Duggan becomes Detroit's first white mayor since the early 1970s. The city is more than 80 per cent black.
Associated Press writers Mike Householder, Jeff Karoub and David Runk contributed to this report.