In Duval County, the big numbers already casting ballots are those voting by mail. Out of the nearly 640,000 registered voters in Duval County, 97,000 people have requested vote-by-mail ballots. At the Election Center on Jacksonvilles Northside, the vote-by-mail ballots were being sorted Monday. For me, its very obvious that mail ballot voting has more opportunity for fraud than early voting or election day voting, Hogan said. He added that when a person votes at a precinct or early voting site, they have to show their ID.