The polls opened at 6 a.m. and most closed at 7 p.m. However, 30 Cook County precincts were given permission to stay open for an additional hour, until 8 p.m., due to late opening. Click here to see the full list of precincts open until 8 p.m.
The Cook County Clerk's office said that lead to a major delay in election results reporting. Cook County didn't begin reporting results until about 9:45 p.m., nearly three hours after most polls closed.
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There are several historic elections in multiple suburbs, with women poised to take the reins for the first time.
Breaking down Illinois suburban elections
Willow Springs, whose population of just over 5,000 residents live tucked along the banks of the Des Plaines River and Chicago Sanitary and Ship canal, have never elected a female mayor in its 129-year history, until now.
"I love this town," said Melissa Neddermeyer, candidate for mayor. "I was born and raised here, and now I'm raising my own three sons here, so it's very near and dear to my heart."
Neddermeyer is running for mayor unopposed. For the past four years, the 40-year-old lawyer has served as the village's only female trustee.
"It's nice to see how so many women are taking on leadership roles, so I'm proud and honored our community seems to be on that is supportive of women in leadership roles," Neddermeyer said.
Residents headed to the polls Tuesday said it was about time, especially in a town that long ago had a reputation for organized crime and corruption.
"I have not seen a woman on the ballot in all the years I've lived here," said Connie Kent, voter. "I think women are steeling out because they feel they have the right to."
And it's not just Willow Springs. Another historic election is being held in Flossmoor, where voters will elect a woman as mayor for the first time. Doctor Lakshmi Emory and Michelle Nelson are running to replace Mayor Paul Braun, who is retiring.
And if Tiffany Henyard wins, she will become south suburban Dolton's first woman mayor.
In Aurora, incumbent Mayor Richard Irvin is being challenged by Alderman Judd Lofchie and John Laesch. Irvin was elected in 2017 and is Aurora's first African American mayor.
In Broadview, Mayor Katrina Thompson is being challenged by Sherman Jones. Thompson is the village's first female African American mayor.
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COVID-19 issues expected to drive voters to suburban polls
For a full list of Cook County races, visit the county clerk's website. For more information, visit the Illinois Board of Elections website.