"I have people tell me that Bryce Harper, really, would prefer to play for the Cubs," Gammons said.
As things stand, Harper isn't scheduled to become a free agent until the winter of 2018 after the Nationals signed him to a one-year, $21.6 million deal in May to avoid arbitration.
That agreement was key because it will give the Nationals another year-plus to exclusively negotiate with Harper as the two sides attempt to hammer out a long-term deal.
"I think it's huge," Harper said after signing the deal, according to the Washington Post's Chelsea Janes and Jorge Castillo. "We're able to go into the offseason and worry about different things. We're able, as a team and this organization, to just go out and not have to worry about me going into arbitration for another year or anything like that."
As far as the Cubs are concerned, Gammons noted trying to balance a mammoth deal for Harper with a future extension for third baseman Kris Bryant—who is under team control through 2021—would prove rather challenging.
"Somehow I don't think it's going to be affordable to have Bryce Harper and Kris Bryant on the same team," Gammons said. "It's a great idea, I'd love to see it. I respect them both so much, personally and professionally. But I don't think it's going to ever happen."