Washington (CNN) Democrats say they fear the Supreme Court's decision to allow Ohio's aggressive purge of its voter rolls will lead to similar moves in other states -- potentially keeping people who might be motivated to turn out and vote against President Donald Trump away from the polls.

In a 5-4 ruling, the Supreme Court ruled that Ohio isn't violating federal law with its method of removing names from the state's voter rolls.

Those who are inactive for two years -- which could mean skipping a federal election -- are mailed confirmation notices. Those who ignore the notices or don't update their registration for the next four years are removed.

Democrats and critics of the law say it fits into a national trend of limiting urban, poor and young voters' access to the polls through steps like voter ID laws, limiting early voting hours and locations, consolidating polling places and more.

"President Trump's re-election campaign is completely staked on the success of voter suppression laws like this one," said Jason Kander, the former Missouri secretary of state now leading the group Let America Vote as he weighs a potential 2020 presidential campaign.

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