“We have been successful in stopping many efforts to prank Senator Graham and the office, but this one slipped through the cracks,” he said. “They got him.” politico.com/news/2019/10/1…
These modestly compromising calls with Graham were recorded by persons with suspected ties to Russian intelligence in early August. It's now early October. Graham has recently made noises opposing Turkey's incursion in Syria... is that why we're hearing about it now?
How much other material do these Russian 'pranksters,' or Russia's intelligence services (if those suspected links prove to be real links), have warehoused on Graham and other members of Congress?
Just for posterity, this is sourced directly to the Russians with suspected ties to the country's intelligence services. 
