It's been estimated that more people are struck by lightening each year than there are cases of someone voting illegally.
This is an excerpt from the item below:
Because voter fraud is essentially irrational, it is not surprising that no credible evidence suggests a voter fraud epidemic. There is no documented wave or trend of individuals voting multiple times, voting as someone else, or voting despite knowing that they are ineligible. Indeed, evidence from the microscopically scrutinized 2004 gubernatorial election in Washington State actually reveals just the opposite: though voter fraud does happen, it happens approximately 0.0009% of the time. The similarly closely-analyzed 2004 election in Ohio revealed a voter fraud rate of 0.00004%. National Weather Service data shows that Americans are struck and killed by lightning about as often.
http://www.brennancenter.org/content/resource/policy_brief_on_the_truth_about_voter_fraud/

OCU