I actually just put my rep's number into my cell phone earlier today. But, I put his DC number in. Is there a reason I should be calling his local office vs his DC office? I want to be as effective as possible.
Here is the logic/reasoning behind calling the local office vs. the DC office.
The DC office is staffed with people trying to run the Congressman's affairs, schedules, policy, etc. When their phones start ringing, whichever intern is charged with answering the phone just starts grabbing extra people for a few minutes to take calls. Then, as soon as possible, the extra people go back to what they are doing.
Whereas, the Local office is staffed with people who are hired to take phone calls from constituents and to listen to constituents. (Solve problems with Social Security, etc...). So, the local staffers are a bit more atuned to their neighbors who start calling.
Plus, somebody out in the local office starts getting overwhelmed with calls, they start passing that up the chain to DC, and try and convince the DC office that something is happening in the District. The DC office just assumes that all phone calls are part of some organized group and just mark it down as "those guys are against us again".
At the end of the day, the calls will be logged / counted as "Opposed HR 621" either way, the extra oomph is when you can get internal staffers to start talking about the number of phone calls disrupting their normal, sleepy day.