Senate Democrats' campaign spending group is wading into Mississippi's Senate race for the first time this cycle.

Michigan's closely contested Senate race has become deeply personal for some voters.

President Donald Trump is heading to Kansas on Monday and Iowa later in the week, the latest in a series of stops where he's trying to energize his base in the final weeks before the midterm elections. The economic strain is becoming a growing political concern for Republicans in states they have long dominated.

Economic struggles are becoming a significant political issue for Republicans in states long considered party strongholds

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Federal authorities are investigating letters that have been mailed to congressional and election offices nationwide and are urging recipients to treat the mailings as "potentially hazardous."

The shifting money in the final weeks of midterm campaigns points to a defensive posture by Republicans and new aggression from Democrats, who aim to capitalize on President Donald Trump's weak approval ratings.