Here's what Jon Husted, our Republican Secretary of State, said about 2012 voter fraud in a report earlier this year.
http://www.sos.state.oh.us/SOS/mediaCenter/2013/2013-05-23.aspxHighlights: 625 recorded cases of "voting irregularities", of which also include reports alleging voter suppression. Of these only 135, including those referred by the SoS, were referred to county prosecutors for potential charges.
Just today I spoke to a reporter for a major newspaper who called our office regarding the status of some of the cases referred here, as he's doing a story on the outcome of such referrals. He said thus far it appeared relatively few of the 135 referrals have resulted in charges due to lack of evidence voter fraud occurred.
So a few hundred reported "irregularities" not involving voter suppression, of which only 135 were found worthy by local boards of elections or the SoS to warrant possible prosecution, and only a few of those were found to have merit sufficient to prosecute. Out of over 5 and a half million votes cast.
What does all this tell us? To quote Secretary Husted (R-OH):
“This report demonstrates that voter fraud does exist; but it is not an epidemic,” Secretary Husted said. “More importantly, our effort to look into irregularities and root out voter fraud sends a strong message that no amount of fraud is acceptable. If you cheat, you will be caught and held accountable.”
“While it is apparent that incidents of voter fraud have occurred and we must remain vigilant, it is also clear that the safeguards we have in place worked in the majority of these cases,” Secretary Husted said.
Also worth noting from the report: In a majority of the cases in which a voter was found to have cast multiple ballots in Ohio, only one of those ballots was ultimately counted.
In summary, the current system of diligently rooting out and prosecuting the rare cases of vote fraud apparently works.