ISBE: At least 300K mail-in ballots may arrive through Nov. 17

ILLINOIS (WAND) - At least 300,000 mail-in ballots could arrive in Illinois through Nov. 17, which state election leaders said could affect election outcomes. 

In tweets, the Illinois State Board of Elections said its pre-election unofficial count found there were over 520,000 mail ballots that had not been returned. That number lowered after the ISBE said it learned before Election Day at least 50,000 mail ballots were returned by voters who instead voted in person. 

The number drops even further after officials said they learned from local authorities many Election Day voters were turning in their ballots to vote in person. 

"Based on this, our best estimate is that 300,000-400,000 mail ballots could arrive through Nov. 17 and affect election outcomes," an ISBE tweet said. "Those figures could change significantly depending on the true number of mail ballots surrendered today."