Republicans are spending the final week ahead of the midterm elections defending historically red Senate seats that have suddenly become competitive, according to federal filings and sources familiar with the matter.

A significant focus is now on four Senate races in ​K​ansas, ​South Carolina, ​Nebraska, and even ​Mississippi, all traditionally red seats, in what’s ​an ominous development for Republicans in their effort to at least keep control of the upper chamber .

Trump operatives tell Inner Loop that they do not expect ​Democrats to win those Senate seats and that they have ​mainly directed GOP outside groups to spend there to ​​help boost incumbents that only have a narrow lead.

But ​t​he operatives also concede that they are having to divert an increasing amount of resources ​to those states—states that president Donald Trump carried by double digits in 2024 and where Republicans never dreamed of having to spend tens of millions of dollars.

In total, in the penultimate week of the campaign, the…