In particular, they raised concerns about canvassers’ submitting an inordinate amount of suspect data. That data, some of which NBC News has reviewed, includes entries submitted far from the home or while canvassers are logged into Wi-Fi networks — telltale signs that a door was not knocked on, sources said. In addition, a video explaining how to “spoof” one’s location while submitting data drew attention  in Nevada and Arizona, raising further concerns.