Before Michigan's 2006 gubernatorial primary, an East Lansing direct-mail consultant named Mark Grebner decided to shame nonvoters. He sent citizens copies of their own publicly available voting histories, along with those of their neighbors, and said that he would deliver an updated set following the election. In response, Mr. Grebner received death threats, but his tactic worked. Those whom he targeted were 20% more likely to show up at the polls than those who received a standard get-out-the-vote reminder.

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