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Chance the Democrat wins (19.3%)
Chance the Republican wins (80.7%)
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+12.2
Adjusted polls
D+1.5
CANTOR
D+1.2
Fundamentals
R+6.3
Experts
R+11.5
Lite
R+6.4
Classic
R+6.4
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected three polls for the Minnesota 8th. 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 | Radinovich | Stauber | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 11-14 10/11-14 | Siena College/New York Times | 507 | LV | 1.40 | 34% | 49% | R+15.7 | — | <0.1 | 0.3 | R+15.9 |
Sep. 27-30 9/27-30 | Victoria Research & Consulting D | 400 | LV | 0.41 | 45% | 44% | D+1.0 | — | <0.1 | 5.2 | R+4.2 |
Sep. 6-9 9/6-9 | Siena College/New York Times | 504 | LV | 0.08 | 44% | 43% | D+1.0 | — | 0.2 | 0.3 | D+0.6 |
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-7 | 83 | — | |
MI-1 | 76 | R+12.6 | |
MN-7 | 71 | D+13.8 | |
WI-3 | 71 | — | |
MI-4 | 67 | — | |
MI-7 | 65 | R+6.6 | |
IA-4 | 65 | R+6.1 | |
WI-6 | 64 | R+15.2 | |
ME-2 | 63 | D+1.1 | |
NY-21 | 63 | R+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 | 8.0 | MN-8 is 10.1 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 Obama in 2012. |
Previous incumbent's margin in last election | 0.1 | A Democrat won by 0.6 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 | 0.9 | As of Oct. 17, Joe Radinovich had raised $1,425,000 in individual contributions (56% of all such contributions to the major-party candidates); Pete Stauber had raised $1,125,000 (44%). |
Candidate experience | 0.0 | Both Radinovich and Stauber have previously held elected office. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | D+1.2 |
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+6.7 | R+6.1 | |
Inside Elections | R+6.7 | R+5.8 | |
Sabato's Crystal Ball | R+6.7 | R+7.1 | |
Average | R+6.7 | R+6.3 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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