Remember ACORN? Yes, well, the Republicans are now doing the same thing that so outraged them...
A consulting firm engaged by the RNC has been filing voter registrations with county supervisors of elections that have forged signatures. The firm claimed that a "bad apple" was responsible -- but this was exactly what happened with ACORN 4 years ago, and the Republican establishment united in a move to defund and effectively kill ACORN as an institution.
Ironically, at the same time that these forged registrations have been submitted by Republican operatives, another Tea Party-related firm was filing petitions with the state against so-called "dead" voters it had "identified" that were still on the rolls. It turned out, of course, that supervisors of elections were already culling their records of dead registrants as part of their ordinary voter roll duties (remember, dead people don't notify the state that they can't vote anymore); more importantly, some supervisors pointed out that there was no evidence of any dead voters having cast votes. That didn't stop the right-wing blogosphere from leaping to the conclusion that a) all these voters who were dead had cast votes after their deaths, and b) that they were all liberals who had voted for Obama.
You will note that Democrats, as a whole, are not beating the drums for a war on voter fraud. That's because voter fraud is a virtually non-existent problem; historically vote tampering has occurred when fake ballots are inserted into the record, or valid ballots are discarded or destroyed. Neither involves voters impersonating other voters.
Republicans will tell you that voting is a sacred right to be protected, yet they discredit their own case every time they engage in manipulations of voter rolls. Their claims that voter fraud is a liberal-inspired problem collapses with each new revelation.