Ms. Loeffler and Ms. Greene exchanged pleasant chitchat near the front door. Later, Ms. Loeffler, who was appointed to her seat last year and must win an upcoming special election to keep it, grabbed a microphone and talked about finishing the wall on the Mexican border, the “fake news” that would never intimidate her and the “dangerous Marxist movement called the Black Lives Matter political organization.”

A reporter asked Ms. Loeffler whether she supported Ms. Greene, and whether she denounced QAnon.

“Marjorie is fighting to defeat socialism; that’s what I’m focused on,” Ms. Loeffler said, adding, “I just thank her for coming out.”

It is a long way from hosting soirees at Descante to joining forces with a right-wing conspiracy theorist at a beer hall. But it is a journey that Ms. Loeffler has undertaken in earnest as she seeks to conform to the tastes of Donald Trump’s Republican Party — just one of the many establishment Republicans who have embraced Trumpism in recent years.