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Chance the Democrat wins (69.4%)
Chance the Republican wins (30.6%)
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.
D+4.1
Adjusted polls
R+4.5
CANTOR
D+2.6
Fundamentals
D+2.6
Experts
D+2.7
Lite
D+3.0
Classic
D+2.9
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected three polls for the Illinois 14th. 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 | Underwood | Hultgren | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 31-Nov. 4 10/31-11/4 | Siena College/New York Times | 428 | LV | 1.58 | 49% | 43% | D+5.2 | — | <0.1 ![]() | 0.3 ![]() | D+5.0 |
Oct. 3-8 10/3-8 | Siena College/New York Times | 501 | LV | 0.11 | 43% | 47% | R+4.8 | — | <0.1 ![]() | 0.3 ![]() | R+5.1 |
Apr. 16-17 4/16-17 | Public Policy Polling D | 682 | V | 0.00 | 41% | 45% | R+4.0 | 0.1 ![]() | ![]() | 1.9 ![]() | R+5.0 |
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. | ||
---|---|---|---|
MI-8 | 71 | D+2.6 | |
MN-2 | 70 | D+6.1 | |
MI-11 | 70 | D+4.6 | |
OH-12 | 67 | R+3.1 | |
IN-5 | 66 | R+6.6 | |
WI-1 | 64 | R+2.7 | |
PA-1 | 64 | D+0.5 | |
KS-3 | 63 | D+9.8 | |
PA-6 | 63 | — | |
IL-6 | 62 | D+1.0 |
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 | Randy Hultgren has been elected to 4 terms. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 3.6 | IL-14 is 9.8 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 | 7.3 | Hultgren won by 18.6 percentage points in 2016. |
Generic ballot | 7.0 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 8.1 | As of Oct. 17, Lauren A. Underwood had raised $3,333,000 in individual contributions (82% of all such contributions to the major-party candidates); Hultgren had raised $740,000 (18%). |
Incumbent's voting record in Congress | 2.1 | Hultgren has voted with Republicans 87% of the time in roll-call votes in recent sessions of Congress. Candidates who vote with their party very frequently tend to underperform at the ballot booth, other factors held equal. |
Challenger experience | 0.7 | Underwood has never held elected office. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | D+2.6 |
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 | EVEN | D+0.6 | |
Inside Elections | EVEN | D+0.9 | |
Sabato's Crystal Ball | D+6.7 | D+6.3 | |
Average | D+2.2 | D+2.6 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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