Mother Jones:

The issue made national headlines in 2000, when Republican officials in Florida alleged that thousands of people with felony records were illegally registered to vote and needed to be removed from the rolls. African Americans made up only 11 percent of registered voters in the state but 44 percent of those on the purge list, which turned out to be riddled with errors. After the election, the state conceded that 12,000 eligible voters had been wrongly labeled as ex-felons and barred from voting. That was 22 times George W. Bush’s 537-vote margin of victory over Al Gore in Florida.

Active voter suppression and the result.