“It seems to me like the governor of Georgia made a terrific appointment,” McConnell said. “She will be an incumbent Republican senator. We will all be behind her. Sen. [Todd] Young has already made it clear the NRSC is going to be behind her. I’m going to be behind her, and I’m confident that someone we’re working with every day will enjoy total support from the Republican conference.”

The McConnell-aligned Senate Leadership Fund is also expected to back Loeffler.

Trump’s allies have attacked Kemp for spurning Trump’s advice to choose Collins, raising the prospect of a contested primary in a critical Senate race next year. Such divisions backfired in 2017 when establishment support for Luther Strange, who was appointed to the Senate from Alabama, was not enough to defeat Roy Moore, eventually costing the GOP a seat. But Republicans argue that Loeffler is stronger and lacks the baggage that Strange brought to the Senate and the subsequent special election campaign.