Instead of simply displaying the phonenumbers of the local Congressmen, they could use a simple Grassroutes widget (http://grassroutes.us/). OccupyWallSt.org and Twitpic.com used the widget during the SOPA blackout.
Reports like these don't take into account active users. And even when they do, they define "active" very vaguely, as in the case of Twitter's 140 million active users.