Officials said they expect a big increase with the expansion in early voting sites.
"Just wanted to get it out-of-the-way and make sure that my vote counts," voter Layra Trylong said.
Chicago residents can now go to any early voting site in the city across all 50 wards to cast their ballot.
Voting also expands Monday in surrounding counties including suburban Cook, DuPage, McHenry, Will, Kane, and Lake County Illinois.
"If given the opportunity, I early vote every time," Tiajauna Gordon said. "Because it's easier to just come in, avoid the mad rush, because there's going to be one, and I do my civic duty."
Experts say about 50% of people vote before Election Day either in person or by mail.
RELATED: ABC7 Chicago Voter Guide
If you are going to vote by mail, election officials urge you to do it now, so you have plenty of time to return your ballot.
"Currently, there have been over a quarter of a million ballots requested by mail and nearly 54,000 vote by mail ballots returned," Chicago Board of Elections Chairwoman Marisel Hernandez said.
All requests to vote by mail must be submitted by October 31 and ballots must be postmarked by Election Day, November 5.
"You never know what's going to happen in your life and it's always a good idea to get in and get it over with," Trylong said. "That way you know your vote counts you know who you want to win has a better chance."
If you still need to register to vote, you can do so here in-person through Election Day at select polling sites.