State and local plans for Election Day include how to react to potential ICE raids, misbehavior by federal election monitors and attempts to seize votes or machines.

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The 44th president sharply criticized Mr. Trump, who hit back later in the day. Mr. Obama also assailed Vivek Ramaswamy, the Republican nominee for governor of Ohio.

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But about half expressed concerns that Republicans could try to overturn the results, a New York Times/Siena poll found.

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