President Trump campaigned Monday in Mississippi, as he continued a closing midterm rally blitz that has highlighted Republicans' challenges ahead of an election that could drastically shift power in Washington.

Vivek Ramaswamy’s dirty political schemes are making history. The Ohio Republican gubernatorial nominee’s boorish ad campaign against Democratic candidate Dr. Amy Acton has inspired one of Ohio’s oldest newspapers, the Cleveland Plain Dealer, to break company policy in Acton’s favor. The paper had stated a few months ago it would not make political endorsements, including in the governor’s race. But on Sunday, its editorial board published a...