UPDATED 09/25/12 1:02 p.m.
CHICAGO (CBS) -- Tuesday is National Voter Registration Day, and officials in Cook County are joining the effort to get everyone onboard.
"We're participating with about 700 organizations around the country, and today particularly at all the courthouses in Cook County – including downtown, in the offices of 69 W. Washington and City Hall – you can register to vote today between 9 a.m. and 5 p.m., Cook County Clerk David Orr said Tuesday morning. "So come out and get it done today."
LISTEN: WBBM Newsradio's Bernie Tafoya reports
There are many circumstances under which a voter may need to register, or re-register. Young people who are turning 18 by Nov. 6 may register now and must do so to vote in the November election, and people who have moved or changed their surnames to a marry name must re-register.
Orr estimates that 20 to 25 percent of Cook County residents are not registered to vote, but now, his office is bringing in many new registrants.
"Thousands are coming in as we speak," Orr said, "and we have until October 9 – two weeks from today – as the last formal day of registration. And there's a lot of activities going on – people can go to their local libraries, go to their local town halls and so forth, and today's a real good chance to do it."
Orr emphasized the need to get registered in time.
"Our last presidential election – we now know about 6 million people who wanted to vote didn't get registered in time," he said.
Later Tuesday morning, Orr and Cook County Board President Toni Preckwinkle stood next to a registration table at the Markham Courthouse, encouraging people to register by the deadline in two weeks.
Orr says he has seen registration picking up in the last couple of days, with about 10,000 to 15,000 more suburban registrations.
Anyone who needs to register to vote in Cook County may do so at the downtown locations Orr mentioned, or at any of the five suburban courthouses:
• Skokie Courthouse, 5600 W. Old Orchard Rd., Room 149, Skokie;
• Rolling Meadows Courthouse: 2121 Euclid Ave., Room 238, Rolling Meadows;
• Maybrook Courthouse: 1311 Maybrook Square, Room 104, Maywood;
• Markham Courthouse: 16501 S. Kedzie Ave., Room 238, Markham;
• Bridgeview Courthouse: 10220 S. 76th Ave., Room 238, Bridgeview.
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