This is a followup to an earlier article in which Barry Loudermilk, the Republican congressman for GA-11, and an avid Trump supporter, made an aside in which he claimed that Jimmy Carter had asked the Russians to interfere in the 1980 election.
In a February town hall teleconference, Loudermilk made a lengthier claim to that effect. A commenter here pointed me to an op-ed on the conservative website NewsMax by Michael Reagan, Ronald Reagan’s son, which makes a similar claim in December of 2016. I suspect that the NewsMax article is where the claim became popularized.
Here’s my article, including a link to the audio of Loudermilk making the claim. It also has a link to the NewsMax article that I think is probably the source of the assertion.