CHICAGO (CBS) — Worries over the coronavirus kept many Chicagoans away from the voting booths.

And the number of ballots cast was down compared to the last primary election in 2018.

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According to Jim Allen of the Chicago Board of Election Commissioners, preliminary results show that with 477,444 ballots cast, turnout was a little above 31%. Most of those who did turn out were Democrats with 460,465 and almost 17,000 Republicans who cast ballots.

Allen said early voting sites had to stay open late because of people who were in line at 7:00. Multiple precincts had their sites stay open after 8:30 p.m.

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But out of the 117,813 ballots mailed out, only 43,5078 were returned.

“Which leaves a potential universe of about 74,000 ballots that potentially could be returned with on-time postmark after this morning through March 31. The vote-by-mail ballots received prior to 3:00 p.m. March 16 were processed and included in the counts,” Allen said.

Allen said his staff is still counting provisional ballots.

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The turnout number compares to the March 20, 2018 primary election where more than a million and a half people were listed as registered voters and turnout came in at a little over 32%.