Knowing which Congressional or State voting districts your supporters live in can help you find potential donors, organize volunteers, or mobilize activists to take action. We automatically add this information to contact records by comparing the addresses to voter registration records. Even if there is not an exact match for your contact in the Voter File, we can use what we know about the likelihood for someone at that address to be in a particular voting district to add that data with 95% accuracy.
How does it work?
We base our matching on zip code data. If we can match your contact to someone in the voter database with the same 9 digit zip code, we’ll be able to add all of the voting districts with 100% accuracy. If there is not an exact match, we will then try to fill in the districts using a hierarchical matching logic that looks for voters with similar addresses.
|
Matching data |
Logic |
|---|---|
|
zip9 with Voter File match |
This is a 100% match and we will fill in all district information. |
|
zip9 with no Voter File match |
The address is compared with other voter records from that zip9 address.
We will add district data if more than 95% of the voters with that zip code are in the same district. If voters are split across that particular voting district (such as State Senate or House), we will leave that field blank on the contact record.
This also means that supporters who use PO Boxes or business addresses will be assigned to the same districts as the registered voters that are in that zip code. |
|
zip7 |
If we do not have enough information from the address to determine the zip9, we will attempt to match on the first 7 digits of the full 9 digit zipcode. If 95% of voters with that same zip7 are assigned the same district (CD, HD, or SD), we will add those values to the contact record. |
|
zip5 |
If we do not have enough information from the address to determine the zip9 OR zip7, we will switch to a zip5 comparison. If 95% of voters with that same zip5 are assigned the same district (CD, HD, or SD), we will add those values to the contact record.
Zip5 is most often used whenever a supporter gives you an address that is not recognized by the USPS (either because there is no delivery there or because it is too new to have the zip+4 assigned). It will also be used whenever you have a city and zip but no street address. |
Examples
|
Available data |
Example address |
Matching logic |
Contact record example (All Details view) |
|---|---|---|---|
|
zip9 available with Voter File match |
30 Chester St |
Someone is registered to vote with this address, which means we can say with 100% confidence that this record should be assigned the Congressional, State House and State Senate districts. |
|
|
zip9 available, but no Voter File match |
40 Glendale Rd |
No one is registered to vote with this address, but 95% of the voters with that same zip7 (01236-97) live in CD 008, HD 045, and SD 030. Therefore, we can say with 95% confidence that this supporter should be assigned those 3 districts. |
|
|
zip9 available, but no Voter File match |
305 Turnpike St |
No one is registered to vote with this address, but 95% of the voters with that same zip7 (02375-17) live in CD 004 and SD 025. Therefore, we can say with 95% confidence that this supporter should be assigned those 2 districts. In this case, we cannot assign an HD to this supporter/address due to the fact that this zip7 spans multiple State House Districts. |
|
|
zip9 is not available |
North Andover, MA 01845 |
We don't have a street address, so we cannot determine the zip9, but 95% of the voters with that same zip5 live in CD 006. Therefore, we can say with 95% confidence that this supporter should be assigned that 1 district. In this case, we cannot assign an HD nor an SD to this supporter/address due to the fact that this zip5 spans multiple State House and State Senate districts. |
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