I had been planning to cover this a bit, but it looks like New Donkey has taken care of some of it for me:
I should have known when George Will started writing columns about the dastardly threat of voter fraud that something big was in the works. And sure enough, the conservative media echo chamber is now vibrating from a cacophany of warnings that Democrats are trying to steal the presidential election by fradulently registering ineligible voters.
What's happening here is an effort to soften up the news media and the public for a truly audacious, and perhaps even desperate, gambit by the Republican Party that appears to be planned for election day: wholesale challenges to minority voters in battleground states in an effort to either (1) intimidate or demoralize likely Democratic voters, or (2) lay the groundwork for one of those Bush-v.-Gore-enabled retroactive legal actions aimed at reversing an adverse result. More likely, the aim is (3) both.
Read the article for more specifics.
As I've mentioned here previously, when the GOP starts charging something about Democrats (e.g. "They're trying to scare voters!", "They're intolerant of free speech!", etc.), it's a virtual guarantee that it's something they are either currently doing or plan to do themselves. For years now, they've honed this pre-emptive attack on others for what they are actually doing themselves to an art form. Will the media and the voters be smart enough to recognize that this time around?
(Hat tip Bryan for the link!)