I don't know, something about getting people out-of-district to donate to a local representative seems distasteful to me. Like, on a very local level, it was discovered a lot of suburban residents were donating to a mayoral candidate here who wanted to abolish residency requirements for city jobs. A policy that would be great for anyone living outside the city, but horrid for the city itself which already has a massive wealth and brain drain. That candidate lost, in large part I think because people don't take well to finding out the rich folks are messing in their politics. Instead the guy who wanted to institute a grant program so cops, teachers, and firefighters could buy houses in the same neighborhoods they worked in won.
I know that's clearly not the case here, but it does open the door for people to screw with the elections in other areas to institute policies more favorable to themselves (and less so to the people actually living there). I always wondered why all donations don't have residency requirements (like how only a US citizen can donate to a presidential campaign.)