Plaintiffs put up by liberal lawsuit shops routinely claim that ID laws endanger the rights of hundreds of thousands, but lawsuits in Indiana and Georgia were dismissed because they couldn't produce a single eligible voter who'd been turned away due to the ID requirement.

WSJ: Review & Outlook: Holder's Voter ID Fraud

In addition, the report alleges that an "overzealous" statewide campaign to reduce voter fraud resulted in disproportionately denying eligible African-American voters from casting ballots on Election Day.

CNN: Report: Florida 'grossly derelict' in 2000 vote

But even in the race's eleventh hour, strategists in both parties are struggling to figure out whether turnout will be closer to 2008 levels, when nearly 70% of eligible Wisconsin voters participated in the presidential election, or 2010, when voter turnout dropped to 49%.

CNN: Walker's fate in Wisconsin comes down to ground game

One is voter registration, which is at a record high, with 2.9m more eligible to vote this year than at the last election in 2002.

ECONOMIST: France's presidential race