"What happened next Mr. Barnes has largely kept secret for nearly 43 years. Mr. Connally, he said, took him to one Middle Eastern capital after another that summer, meeting with a host of regional leaders to deliver a blunt message to be passed to Iran: Don’t release the hostages before the election. Mr. Reagan will win and give you a better deal."

https://www.nytimes.com/2023/03/18/us/politics/jimmy-carter-october-surprise-iran-hostages.html