Lightfoot has held several positions in and out of government. She was an assistant United States attorney, a senior equity partner at Mayer Brown LLP and, most notably, the president of the Chicago Police Board, an independent civilian panel.
Some on the left, including Preckwinkle, criticized her as not being progressive enough, noting she made millions as a corporate lawyer representing corporate clients.
She and Preckwinckle earned spots on the runoff ballot after they garnered the most votes among 14 candidates, including Richard M. Daley's younger brother Bill, in a February election. Lightfoot will replace Rahm Emanuel, who announced in September he was not seeking a third term as mayor.
Voters saw Lightfoot as the anti-establishment choice compared with Preckwinkle, who was a city council member, or alderman, for almost 20 years before becoming Cook County board president in 2010.
"Lightfoot will bring more change because Preckwinkle is connected to the old-boys club, the establishment," said retired mailman Gary Muckle, 77, after voting for Lightfoot this weekend at a polling place on the city's north side.
"We will have to see what happens now. Lightfoot is not beholden to anyone," he said.
Lightfoot will also face a raft of thorny problems such as reforms to the police department, rampant gangs and violent crime and a spiraling budget deficit fueled by escalating pensions.
Emanuel leaves as corruption continues to seep throughout city hall. Just this year, Alderman Ed Burke, a long-time political powerhouse in Chicago, was charged with extortion, Alderman Willie Cochran pleaded guilty to wire fraud and it was revealed Alderman Danny Solis was recently under investigation for corruption.
Burke, who has been an alderman for 50 years, won re-election in February.
In all, federal prosecutors racked up 246 public corruption convictions in the Northern Illinois District, which includes Chicago, from 2010 to 2017. That is 80 percent more than in the Southern District of New York, located in Manhattan, according to a report from the Department of Political Science at University of Illinois at Chicago.
"The race turned on reform of Chicago politics and moving towards a new Chicago," said Dick Simpson, a professor in the department, who studies Chicago politics, noting that 33 city council members have gone to jail over the last four decades.
"There seems to be a desire to make reforms so that the continuing pattern of corruption ... would change permanently," said Simpson, a former city council member.
