"A lot of people have made up their minds. I don't think the debate will sway them one way or another, and I'm one of those people," said voter Chris Tapas.
Fifty-one sites in the city and 44 sites in suburban Cook County opened Monday, and there could be strong turnout during the early voting period because few voters remain undecided.
"I think if you look at several elections since we have had early voting, you're going to see in terms of the percentage of overall votes, a steady climb," said Langdon Neal, Chicago Board of Elections.
It appears the surging numbers caused problems at one South Side early voting site.
"I think they weren't expecting this many people, but as I recall in 2008, we had people all the way down 63rd," said Andrea Frank, Chicago Park District.
A small room and only six voting machines had many at the Jackson Park District Fieldhouse waiting two hours to vote.
"People were wrapped around the building, and I seen elderly people getting frustrated and started to walk away to their car," said Lorraine Ousley, early voter.
A spokesperson from the Board of Elections says the turnout has broken first-day records and adds that the board is looking at steps to alleviate the problem, including seating for those waiting to vote and adding more voting machines in some polling places. And while it's possible that the number of votes sent in by mail will increase because of a state law in 2008 that makes it more convenient; the law now says anyone can vote by mail. In the last presidential election, voters needed a reason to do so. There is a question of how it will impact the outcome of the election.
For the few undecideds, it may close the deal for them and may make up their minds for them, but I suspect most people already made up their minds," said Laura Washington, ABC7 political analyst.
Early voting ends November 3. Those ballots cannot be changed once they are cast, and they will not be counted until after the pole polls close on Election Day.
In 2008, roughly 260,000 people voted early in Chicago. In suburban Cook County, it was roughly 226,000.
However, the number of overall voters is down. Election officials say 2008 was a historic year which will be hard to match. Also, the city has lost some population.
The Associated Press contributed to this report.