Graff's position in Trump's orbit recently gained attention after Donald Trump Jr. released a June 2016 email exchange with British publicist Rob Goldstone leading up to the meeting with Russian attorney Natalia Veselnitskaya at Trump Tower.
“I can also send this info to your father via Rhona," Goldstone wrote Donald Jr. in the email, "but it is ultra sensitive so wanted to send to you first.”
Graff was not on the email chain and it's unclear if Goldstone ever made direct contact with her.
The president, who has said he does not use email, communicated with associates for years through Graff. "Everybody knows in order to get through to him they have to go through me, so they are always on their best behavior,” Graff told Real Estate Weekly in 2004.
According to sources familiar with Trump's habits, Graff would often receive emails on his behalf and print them out for his review. If Trump felt the need to respond he would write on the print out -- typically with a Sharpie pen -- and hand it back to Graff so should could scan the message and send it on electronically.
Attorney Alan Futerfas, who serves as outside counsel representing the Trump Organization and its employees, says Graff has not yet been contacted by congressional investigators.
"We have yet to receive such an inquiry but will, of course, continue to cooperate with any Committee seeking information,” Futerfas told ABC News when asked about the possibility of Graff being questioned or asked for records by investigators looking into the Russia matter.
Graff has not been accused of wrongdoing.
Senate and House Intelligence Committee aides declined to comment on the record about whether Graff has been contacted or would be soon.
“I think we should hear from every individual who is mentioned in the Don Jr. email chain to understand what was happening,” said Rep. Eric Swalwell, D-California, a member of the House Intelligence Committee.
Senate Judiciary Committee investigators, also probing the meeting, are reviewing 20,000 pages of documents handed over to the committee by the Trump Campaign earlier this week, according to a committee aide.
The Judiciary Committee, along with the House and Senate Intelligence Committees, all want to interview Manafort and Trump Jr. in public and private this fall -- along with anyone associated with the meeting.
ABC's John Santucci, Justin Fishel and Jonathan Karl contributed to this report.