NORTH CANTON, Ohio (AP) ¿ Sen. Charles Schumer on Monday asked the Justice Department to review Diebold Inc.'s sale of its U.S. voting-machine business to a bigger competitor, saying he is concerned it could have an adverse impact on American voting.

Diebold, of North Canton, earlier this month announced the sale of its Allen, Texas-based subsidiary Premier Election Solutions Inc. to Election Systems & Software Inc. of Omaha, Neb.

Schumer, chairman of the Senate Rules and Administration Committee, said the sale would give one company control over three-quarters of the U.S. market for voting systems.

"Since this industry provides a product vital to American governance, I am asking that the (Justice Department's) antitrust division examine this acquisition carefully to make sure there is no anticompetitive impact on election officials, states or voters," the New York Democrat said in a letter to Attorney General Eric Holder.

Schumer said a 2003 Congressional Research Service report raised concerns about the consolidation of voting systems.

"The report indicates that having a diversity of voting systems in our country may decrease the likelihood of widespread election fraud," Schumer said.

The Justice Department declined to comment.

Diebold spokesman Mike Jacobson said the transaction is closed and referred questions to ES&S. ES&S spokesman Ken Fields said the transaction will result in stable service and sustainable support for upcoming elections.

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