Re Calling Representatives

I have the good fortune of having 2 Democratic Senators and a Democratic Congressional representative, all of whom are on-board with my legislative preferences. My question is this: Is it worth the effort to call politicians outside my own political venue or do they ignore anything not from their state/district? They always ask my zip code when I call in so I wonder if calling, for example, Lisa Murkowski's or Mitt Romney's office, has any impact at all or if the call is just trashed? Any thoughts?