Between every registered voter and the voting booth is The List. And if you’re not on it, you might not be able to cast a ballot.

One of the biggest changes wrought by the Help America Vote Act is the mandate that every state must have a voter registration database up and working by the Nov. 7 general election. But a dozen states missed the Jan. 1 deadline for finishing their databases, which produce lists of registered voters for every precinct. And four states have been sued by the Justice Department.