I guess it depends on your time frame. After the other shortstops started going off the board, there was a lot of speculation out there that the Cubs preferred Swanson. Heck, you could look up the thread on here if you don't believe it. One of the wonderful things about the internet is that everything stays out there for later review. It's like those replay commercials.
Anyway, there was rumor to be interest from his side from the very beginning because of his wife's association with Chicago. There were a few early rumbles about the Cubs possibly being interested, but things started getting more vocal in the media as the other shortstops picked destinations.