Different use case

So I want to build a website to find which local officials u have to vote for in local elections in my country.

-The main functionality would be to be able to use the “near me” button to find which offices you have to vote for and who are the candidates
-The problem here is that I cannot use the regular near me since provinces are irregular and not necesarily because an “Office Listing” is closest means it is the voting district u belong to
-A way to draw limits to divide the country in regions would be the “solution” or something similar to that

I suppose u could also just have the users select their region from the map instead of going thru such headaches. Still tho, I wanted to know if something like this is feasible using GD and have the user just press the “Near me” button to find the info and the options he/she needs.. I was wondering if something like this would be possible and if u could point me in the right direction. I understand a lot of custom code may be required.