It’s no longer just Arizona, Colorado, and Maine, blue-trending battlegrounds where Republicans were prepared for a dogfight from the beginning of the 2020 cycle — or purple states such as Iowa and North Carolina. They are now looking over their shoulder in typically ruby-red territory such as Alaska, Georgia, Kansas, Mississippi, Montana, and South Carolina.

“The numbers are astounding,” GOP operative Doug Heye said. “Republicans are right to be concerned.”…

“I’m worried,” a senior Republican official conceded. “Mississippi — Democrats are pouring in money. South Carolina — it’s for real. Kansas — it didn’t end when [Kris] Kobach lost” the GOP primary. Dan Eberhart, a Republican donor who contributes to Senate candidates, acknowledged the anxiety swirling around the party. “We are being outspent, no two ways about it,” he said. “There are clearly concerns going into the final month.”

To protect their majority, Republicans have been forced to invest money in unusual places.