I've completed the analysis for the 6 new targeted congressional districts in Illinois by going through them precinct by precinct and comparing the performance of past statewide candidates, plus turnout and vote share. Not long after I started this I really wished I hadn't, this took forever but it's pretty interesting data now that it's done.

You can get to this data in the future by going through the VOTE ANALYSIS toolbar at the top. Or you can go to the individual pages directly:

Quick Glance

Here's a quick glance comparison of the difference between the Democratic/Republican candidate by past statewide contest for each district:

IL-08IL-10IL-11IL-12IL-13IL-17Statewide
10SENR +11.26R +12.98R +06.64R +08.52R +18.72R +15.38R +01.59
10GOVR +07.60R +01.16R +04.31R +06.08R +19.99R +14.59D +00.69
10AGD +27.18D +30.74D +29.01D +19.73D +18.25D +22.90D +33.07
10SOSD +39.38D +41.42D +41.35D +27.14D +28.91D +33.39D +42.85
10COMPR +26.29R +21.21R +18.81R +10.04R +24.79R +16.74R +11.74
10TREASR +19.05R +13.39R +12.74R +04.70R +19.97R +09.76R +04.42
08PRESD +14.69D +25.40D +21.01D +10.99D +09.31D +19.37D +25.14
08SEND +34.13D +36.89D +33.34D +30.06D +29.97D +35.27D +39.31
06GOV D +08.14 D +14.74 D +08.31D +10.55
06AG D +50.95 D +33.62 D +32.84D +48.20
06SOS D +32.73 D +24.01 D +24.23D +29.79
06COMP D +30.28 D +27.21 D +27.33D +32.76
06TREAS D +09.03 D +11.67 D +10.53D +12.70
04PRES   D +02.57 D +06.20D +10.34
04SEN   D +33.15 D +38.42D +42.92

Unless something drastically changes I'm probably not going to be in front of a computer crunching numbers on election night, but for any of you preparing a master spreadsheet for a boiler room on any of these races you should have enough here to put together a good system.



The news of the day comes from a We Ask America poll on the Illinois presidential race. There had been some speculation that Illinois was trending in play, but this poll seems to put that speculation to rest. However there are still those who think these poll numbers are flawed in some way so I developed this little app to allow people to enter some performance values by region and compute the statewide total.

You can find historical Democratic and Republican performance by region here if you want some reference on how other past candidates have performed in these regions.

Also, this app defines collars as the traditional 5 collars of Lake, McHenry, DuPage, Kane and Will. For more on that topic see the FAQ here.

h/t



Early voting in Illinois began just a few days ago and in some other states around the country it has been going on for as many as a few weeks now. Most states have some form of early voting with some combination of early vote, vote by mail and/or no-fault absentee voting. The county clerks in each jurisdiction are busy taking record of which voters have already completed a ballot, the clerks must do this to ensure that the same voter doesn't show up to his/her polling place on election day and cast a 2nd ballot, and so we are starting to see some numbers reported both in polling data and in actual numbers voted in media reports. For example this poll in Time Magazine shows that among early voters in Ohio 60% are supporting President Obama while 30% are supporting Governor Romney, and according to this data from the Iowa Secretary of State 542,000 people have requested an early ballot and 376,000 have already returned their ballot. Here is a good site that is trying to aggregate as many of the available statistics and analysis on early voting. While any candidate would strongly prefer to have any and all of their supporters vote as early as possible to ensure their vote is heard and counted it's important to understand that some early votes are more interesting and significant than others. Consider two types of early voters, one we'll call Habitual Voters. These are voters who were 100% certain to vote and couldn't wait to cast their vote. The other type we will call Sporadic Voters. These are voters who were likely or very likely to support your candidate but for whatever reason they don't always make it to the polls. Sometimes they forget, maybe they work multiple jobs at strange hours or perhaps they travel a lot. For whatever reason some voters are just sporadic voters. Sporadic Voters are the voters that most interest campaigns during early vote. A well organized campaign should be taking advantage of the convenience offered by early vote to help their likely supporters take advantage of this convenience and make sure they cast their ballot. A good GOTV (get out the vote) operation should help a campaign by increasing their vote total among supporters by encouraging sporadic voters to vote. However the early voting data reported by polling firms, county clerks and state boards of elections can't distinguish between Sporadic Voters and Habitual Voters. That sort of data just isn't easily available publicly. But the campaigns know. In Illinois, for example, each county clerk (or municipal election authority - there are 8 of them) are required to send a list of voters who have early voted to the State Board of Elections within two days. That data is then aggregated by the State Board and made available to the campaigns who will update their voter files with that data. The campaign voterfiles are sophisticated enough that they can be easily queried to see which voters are Sporadic vs. Habitual Voters and they can keep score on which types of voters have voted and which candidate they are supporting (at this point in a presidential campaign the campaigns know who each voter is voting for with a pretty high degree of accuracy). Both the Republicans and the Democrats have released memos taking credit for their progress on early voting. This memo from the RNC doesn't mention any data relative to sporadic voters, but here's their take:
In the battleground states with available data, Republican AB/EV activity is strong. In addition to raw Republican versus Democrat turnout numbers, there are two key metrics by which we can measure this. First, we can calculate the party's share of AB/EV activity as compared to the party's share of voter registration. The data show the percentage of AB/EV activity from Republicans is greater than the percentage of registered voters which are Republican, indicating higher turnout rates among registered Republicans than among registered Democrats. For example, Republicans are outperforming our share of voter registration in absentee requests and early votes by 5.6 points in Florida, 8.73 points in Ohio, and nearly 12 points in Pennsylvania. Second, we can measure the party's share of AB/EV activity as compared to its share in 2008. In most cases, the data show Republicans making up a larger share of early voters this year than they did four years ago. Democrats make up a smaller share, giving Republicans an important advantage. Across the eight states, Democrats are underperforming their share of 2008 AB/EV votes cast by a net 5.85 percentage points, while Republicans are over-performing their share by 2.13 points, yielding a net swing of +7.98 percentage points for Republicans.
I'd prefer a more data driven analysis, but that's their take. On the other side of the coin is this memo from the Obama campaign field director. I wish they'd make their daily spreadsheets available by state and give us more data but they do have some analysis on Sporadic Voters (defining sporadic voters as voters who early voted in 2012 but didn't vote at all in 2010):
Non-midtermvoters: Across nine battleground states, Democrats have a 19.7 point advantage in ballots cast among non-midterm voters. More than half (51.5 percent) of non-midterm voters who have voted already are Democrats, while fewer than a third (just 31.8 percent) are Republicans.
  • For example, in North Carolina, 51.5 percent of those who have already voted are Democrats, compared with just 25.1 percent who are Republicans. That's a major advantage. And among these non-midterm voters who have voted in North Carolina so far, 87 percent of them are youth (under 35), African-American, Latino, or new registrants (registered after the 2008 election).
This is more useful and interesting data but it's no guarantee of success. Hopefully reporters who are working on early voting stories are asking the campaigns to provide data (not just spin) on the performance and partisanship of sporadic voters who have voted early. Now having said all this it's important to keep in mind that the data is not perfect and it's the larger counties with larger staffs that provide the most reliable data. For example, in Illinois every county clerk is supposed to send their early voting data to the State Board of Elections but I'm certain that many of the smaller counties just don't have the capacity to meet this obligation daily. So the most reliable data is generally coming from the areas with large populations and if you think population and/or population density correlate to specific candidate performance then you should take that into account when trying to understand the data.


I have added some new data to the Redistricting section. Are you interested in finding out which congressional districts overlap with which state senate districts or state rep districts, or even which counties are involved? I've run all the districts through the computer and created this simple utility to give you more information about the districts. Check it out!


Welcome to Illinois Election Data, a data driven website I've created to share and display useful campaign data on Illinois elections. During my time working on campaigns I have amassed a very large number of files on Illinois election data. Having been through this exercise so many times I know how difficult and time consuming it can be to have to build the same data files over and over and I have a lot of sympathy for those who have to do so. I created this site to try to provide a lot of the basic data in an easy to see, understand and use format to help the overworked campaign staffers who work too many hours.

There is quite a bit of information in this site:

  • MAPS - Click on MAPS to select various types of vote total maps with the results color coded on top of Google Maps.

  • VOTE ANALYSIS - Click on VOTE ANALYSIS to see spreadsheet style data on election results, vote share and/or turnout organized by county, ward, township, media market and/or region.

  • BUDGETS - Click on BUDGETS to see monthly line item fundraising and spending for previous campaigns as well as payroll and media buys.

  • REDISTRICTING - Click on REDISTRICTING to overlay various maps to see how they are different. You can look at the new ward, congressional, state house, or state senate boundaries and see how they compare to the old boundaries, or with each other or even with county boundaries.

If you have any questions check the FAQ for more info.

Over time I plan to add more data and occasionally use this blog to highlight or add some depth to some data I find particularly interesting. If you want to keep an eye out for updates to this site feel free to follow its Twitter feed (see right hand sidebar), new posts will automatically be tweeted as well. Enjoy.


© Illinois Electon Data