“Some 7.2 million people are registered to vote in more than one state, according to data obtained this month by a voter-integrity law firm called the Public Interest Legal Foundation. The data come from the Interstate Crosscheck system, a 28-state consortium run by Kansas. The numbers largely are unchanged from 2014, when the database had 7.3 million double-registered voters. “Let’s check. If that’s the case, at least we’ll have appropriate measures to make such a statement.” Considering that nearly half of the states — including the three most populous — do not participate in the voluntary system, Public Interest Legal Foundation spokesman Logan Churchwell said the total number of people in America registered to vote in more than one state could be twice as high or greater. “It could be 20 million,””
Most of the double dippers probably do not vote more than once, but their 2nd vote could be used by someone else to game th system. If every legal vote matters then duplicates should be eliminated.