Political District Matching

Use our District Matcher web application to match your address list to the  2012-2020 reapportioned Congressional, State Senate and State Assembly districts. 

Sign in now and test out a few addresses for no charge. Just create an account and then log right in at: District Matcher .

In 2012 all congressional district and most state legislative district boundaries were redrawn to reflect the changes in the U.S. population as tracked since the last census in 2000.  Redistricting can occur more frequently than every ten years too!  With District Matcher, eMerges will make your address list up to date with the most current state and federal political boundaries.

District Matching using our Registered Voter File – Using the eMerges registered voter file to match a mailing list will yield you binders of information about the voter. You will receive the congressional, state senate and  house districts for a and frequently also the voter’s date of birth, gender, political party affiliation, ethnicity and history of participating in any particular election—including whether they voted provisional or absentee.  Our voter file matching process is done off line, ask for more details.

District Matching using Longitude and Latitude Shape Files  -  This is the most accurate way to assign political districts to any address.  Our process requires that each address be appended with longitude and latitude coordinates.  Our process generates the same level of accuracy that the GPS in a vehicle uses. Be mindful however that although coordinates in the shapefiles have six implied decimal places, the positional accuracy of these coordinates may sometimes be not as great as the six decimal places suggest.

What about using zip+4 to match districts? - In 2007, eMerges was contracted by the United State Postal Service (USPS) Application Research & Development PM Team at the National Customer Support Center of the USPS in Memphis to perform an analysis. We compared zip+4 applied congressional districts to our actual voter file registrations from the State Boards of Elections in Georgia, Baltimore and New York City.  Together with Northrop Grumman and the post office—who better to know—we concluded that the accuracy levels of zip+ matching were 4-6% lower than the eMerges voter files from the State Boards of Elections.  Why did the postal service care? The post office had been deluged with complaints from congressman about their franked mail being misdelivered outside of their districts. For members of congress, it is illegal to mail to registered voters residing outside of their jurisdiction: US Code. Things have not changed since our study, Zip+4 matching is still derided as a budget shortcut that yields unnecessary errors. We recommend that you use either our registered voter file or our geocoding approach to match your political districts. However, we can process using zip+4 if that is your threshold.

Our District Matcher will geocode your addresses and assign district numbers at the rate of about one million per hour—your list can be completed in no time at all. You may match your list online now, simply register and log in at:  District Matcher.

State legislative redistricting files are particularly vexing to manage properly. False assumptions can lead to critical errors.

We Know The Rules. – As Justin Levitt explains, some redistricting plans take effect immediately, changing representation before the next election.  Most redistricting plans take effect upon the next election.  But some state houses change every 2 years, and some change every 4 (and Virginia and New Jersey are in odd numbered years).  Maryland’s on the four-year plan … which is why the new redistricting maps don’t take effect until 2014.

For the plans that “take effect” upon the next election, there’s usually a lag between the election and new reps taking office, for representational purposes.  So as a constituent, my representative is the representative of my old district until new representatives are seated.  Thus, Maryland elections are held in new districts in late 2014, but people are represented by their old representatives (in old districts) until the transfer of power in early 2015. It gets weirder though.

State Senates with staggered terms actually complicate the whole thing even further.  Some state Senates have staggered seats, with half of the body up in 2012, 2016, 2020 and the other half up in 2014, 2018, etc.  Let’s say that last cycle’s version of district 1 represents San Francisco, and district 2 represents Los Angeles.  The new version of district 1 represents Los Angeles, with San Francisco now represented by district 2.   And let’s say that Senator Smith, from district 1, is up for election in 2012, and Senator Lopez, from district 2, is up for election in 2014.

eMerges will help you manage the nuances of redistricting. Call or email now for more information.

Per Record Fees –

Simply register and log in at:  District Matcher.