Alan: It is much easier to persuade people to vote by rewarding legal voters than undertaking the byzantine complexity of arranging voter fraud.
This is particularly true among ghettoized Democrats.
Just announce that "polling place buses" will be centrally located on Election Day and that every voter who gets on board will be rewarded with a free restaurant meal on the way home.
As late as the 1970s this method of "getting out the vote" was common in the South and there is currently no impediment to its resurrection, especially if the designated restaurant agrees to donate the food.
That said, I am also in favor of Mandatory Photo I.D.s which - if intelligently implemented - will result in far more liberal registration than conservative registration.
Pax On Both Houses: Compendium Of Voter Fraud And Voter Suppression Posts