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Chance the Democrat wins (79.2%)
Chance the Republican wins (20.8%)
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+4.6
Adjusted polls
D+4.5
CANTOR
D+5.7
Fundamentals
D+6.3
Experts
D+4.6
Lite
D+4.9
Classic
D+5.4
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected seven polls for the Michigan 11th. 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 | Stevens | Epstein | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 15-17 10/15-17 | Target Insyght | 500 | LV | 1.00 | 48% | 48% | EVEN | — | <0.1 | 1.8 | D+1.8 |
Oct. 10-14 10/10-14 | Anzalone Liszt Grove Research D | 513 | LV | 0.48 | 46% | 37% | D+9.5 | — | <0.1 | 4.0 | D+5.5 |
Oct. 10-13 10/10-13 | Harper Polling R | 400 | LV | 0.65 | 36% | 35% | D+1.0 | — | <0.1 | 4.9 | D+5.9 |
Oct. 1-6 10/1-6 | Siena College/New York Times | 465 | LV | 0.78 | 45% | 38% | D+7.6 | — | <0.1 | 0.3 | D+7.3 |
Oct. 2-4 10/2-4 | Anzalone Liszt Grove Research D | 503 | LV | 0.22 | 42% | 37% | D+5.0 | — | <0.1 | 4.0 | D+1.0 |
Aug. 24-27 8/24-27 | Harper Polling R | 400 | LV | 0.01 | 34% | 29% | D+5.0 | — | 0.1 | 4.9 | D+10.0 |
Aug. 13-16 8/13-16 | Anzalone Liszt Grove Research D | 500 | LV | 0.00 | 44% | 36% | D+8.0 | — | 0.4 | 4.0 | D+4.4 |
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. | ||
---|---|---|---|
IL-6 | 70 | D+1.0 | |
IL-14 | 70 | D+4.1 | |
MN-3 | 69 | D+7.1 | |
KS-3 | 68 | D+9.8 | |
MI-8 | 67 | D+2.6 | |
PA-1 | 67 | D+0.5 | |
MO-2 | 65 | R+4.8 | |
PA-17 | 63 | D+12.5 | |
PA-6 | 63 | — | |
MN-2 | 63 | D+6.1 |
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 |
---|---|---|
District partisanship | 5.1 | MI-11 is 6.4 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. |
Previous incumbent's margin in last election | 0.7 | A Republican won by 12.8 percentage points in this district in 2016. Previous district results are not strongly predictive in races without incumbents. |
Generic ballot | 8.3 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 3.2 | As of Oct. 17, Haley Stevens had raised $2,789,000 in individual contributions (72% of all such contributions to the major-party candidates); Lena Epstein had raised $1,105,000 (28%). |
Candidate experience | 0.0 | Neither Stevens nor Epstein has held elected office before. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | D+5.7 |
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 | D+6.7 | D+7.4 | |
Inside Elections | D+4.4 | D+5.3 | |
Sabato's Crystal Ball | D+6.7 | D+6.3 | |
Average | D+5.9 | D+6.3 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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