Lori Lightfoot, 56, has been elected mayor of Chicago, becoming the first Black woman elected to the office, according to unofficial poll results obtained by the Chicago Tribune.

Lightfoot, who is openly gay, previously served as an Assistant US Attorney and a senior equity partner at Mayer Brown LLP. She defeated Cook County Board President Toni Preckwinkle on Tuesday, capturing the election with a lead of 76 percent to Preckwinkle's 26 percent, the Chicago Tribune reports.

A former federal prosecutor, she received support from the likes of Chance the Rapper during her first run for elected office.

According to the media outlet, Lightfoot's key policies include: passing an ordinance to ensure affordable housing in all wards; reforming police and community relations through a new Mayor's Office of Public Safety; and creating more funding to eliminate homelessness.

The new mayor-elect follows Chicago's controversial two-term mayor and former chief of staff to President Barack Obama, Rahm Emanuel.