An election researcher in Florida found that 15 percent of mail-in ballots sent in for the midterm election by Parkland residents between the ages of 18 and 21 were not counted, exceeding the statewide average, The Washington Post reports.

A shooting at Marjory Stoneman Douglas High School in Parkland in February 2018 killed 17 people, and students there quickly organized, calling for stricter gun laws and holding the March for Our Lives demonstration in Washington, D.C.

Daniel A. Smith, chairman of the political science department at the University of Florida, looked at Florida's open-source voting file, and determined that about 1 in 7 mail-in ballots submitted by college-age voters in Parkland were not counted, because they either didn't arrive in time or were rejected for reasons like not having a signature that exactly matched voting records. Looking at all Florida voters between 18 and 21, Smith found about 5.4 percent of mail-in ballots went uncounted. For all ages, the statewide average of rejected or uncounted mail-in ballots was 1.2 percent, Smith told the Post.

"If you are voting in Florida, and you are young in Florida, you have a good chance of your ballot not being accepted," Smith said. "Imagine going to the ATM and every 10 times you go, instead of spitting out your money, they take it or they lose it." From February 2018 to Election Day, about 250 Parkland residents between the ages of 18 and 21 registered to vote, Smith said, and more than half voted in November, which is an unusually strong turnout of young voters during a midterm election, he told the Post. For more about Florida's highly scrutinized electoral system and the Parkland students upset that their votes weren't counted, visit The Washington Post. Catherine Garcia