Johnson tells The Associated Press that the designation "is simply the right and obvious thing to do," particularly in these times.
The move comes despite opposition from many states worried that the designation would lead to increased federal regulation or oversight on the many decentralized and locally run voting systems across the country.
A declassified U.S. intelligence report released Friday says Russian President Vladimir Putin "ordered" an influence campaign in 2016 aimed at the U.S. presidential election.
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