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Chance the Democrat wins (0.9%)
Chance the Republican wins (99.1%)
We'll be updating our forecasts every time new data is available, every day through Nov. 6.
The Classic version of our model projects a race’s outcome by taking a weighted average of polls of a district (if available), polls of similar districts (CANTOR) and non-polling factors (fundamentals). It is then reverted toward a mean based on long-term trends in midterms and presidential approval ratings.
R+14.6
Adjusted polls
R+10.2
CANTOR
R+17.9
Fundamentals
R+22.1
Experts
R+13.1
Lite
R+15.9
Classic
R+18.0
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected one poll for the Illinois 16th. We’re adjusting poll results in three ways: Polls of registered voters or all adults are adjusted to a likely-voter basis; older polls are adjusted based on shifts in the generic congressional ballot since the poll was conducted; and polls are adjusted for house effects (the tendency for a firm’s polls to lean toward Democrats or Republicans). Polls with larger sample sizes and those conducted by higher-quality polling agencies are given more weight, as are more recent polls.
Adjustments | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
dates | pollster | sample | weight | Dady | Kinzinger | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 27-29 10/27-29 | Change Research | 554 | LV | 1.31 | 41% | 55% | R+14.0 | — | <0.1 | 0.6 | R+14.6 |
Key
A = adults
RV = Registered voters
V = voters
LV = likely voters
= partisan poll
Our district similarity scores are based on demographic, geographic and political characteristics; if two districts have a score of 100, it means they are perfectly identical. These scores inform a system we use — CANTOR, or Congressional Algorithm using Neighboring Typologies to Optimize Regression — to infer what polling would say in unpolled or lightly polled districts, given what it says in similar districts.
Sim. score | Polling avg. | ||
---|---|---|---|
WI-6 | 79 | R+15.2 | |
OH-5 | 79 | — | |
WI-8 | 77 | — | |
OH-2 | 75 | R+13.6 | |
MI-7 | 75 | R+6.6 | |
IN-2 | 75 | — | |
IL-12 | 74 | R+6.9 | |
MI-2 | 74 | R+8.0 | |
KS-2 | 74 | D+0.1 | |
OH-7 | 73 | R+12.2 |
The Classic and Deluxe versions of our model use several non-polling factors to forecast the vote share margin in each district.
Factor | Impact | Explanation |
---|---|---|
Incumbency | 3.2 | Adam Kinzinger has been elected to 4 terms. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 6.5 | IL-16 is 17.9 percentage points more Republican-leaning than the country overall, based on how it has voted in recent presidential and state legislative elections. It voted for Trump in 2016 and Romney in 2012. |
Incumbent's margin in last election | 13.1 | Kinzinger won by 99.9 percentage points in 2016, but did not face major-party opposition. |
Generic ballot | 7.0 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 1.8 | As of Oct. 17, Kinzinger had raised $424,000 in individual contributions (57% of all such contributions to the major-party candidates); Sara Dady had raised $319,000 (43%). |
Incumbent's voting record in Congress | 0.4 | Kinzinger has voted with Republicans 79% of the time in roll-call votes in recent sessions of Congress. |
Challenger experience | 0.7 | Dady has never held elected office. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | R+17.9 |
The Deluxe version of our model calculates an implied margin for each race based on expert race ratings from The Cook Political Report, Inside Elections and Sabato's Crystal Ball; it then adjusts that margin toward its estimate of the national political environment.
Equivalent Margin | |||
---|---|---|---|
Expert | Rating | Raw | Adjusted |
Cook Political Report | R+22.5 | R+21.8 | |
Inside Elections | R+22.5 | R+21.6 | |
Sabato's Crystal Ball | R+22.5 | R+22.9 | |
Average | R+22.5 | R+22.1 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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