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Chance the Democrat wins (26.8%)
Chance the Republican wins (73.2%)
The Classic version of our model projects a race’s outcome by taking a weighted average of polls of the race (if available), polls of similar races (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+8.6
Adjusted polls
R+4.9
CANTOR
D+10.0
Fundamentals
R+6.3
Experts
R+8.6
Lite
R+4.6
Classic
R+5.2
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected 10 polls for the North Dakota Senate election. 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 | Heitkamp | Cramer | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct 27-30 10/27-30 | Fox News | 789 | LV | 2.37 | 42% | 51% | R+9.0 | — | <0.1 | 1.5 | R+7.5 |
Oct 23-24 10/23-24 | Trafalgar Group | 1,498 | LV | 1.49 | 46% | 55% | R+9.0 | — | <0.1 | 1.4 | R+7.5 |
Oct 12-19 10/12-19 | Strategic Research Associates | 650 | LV | 0.69 | 40% | 56% | R+16.0 | — | <0.1 | 2.4 | R+13.6 |
Sep 29-Oct 2 9/29-10/2 | Fox News | 704 | LV | 0.14 | 41% | 53% | R+12.0 | — | <0.1 | 1.5 | R+10.5 |
Sep 17-27 9/17-27 | Strategic Research Associates | 650 | LV | 0.07 | 41% | 51% | R+10.0 | — | 0.1 | 2.4 | R+7.7 |
Sep 8-11 9/8-11 | Fox News | 701 | LV | 0.02 | 44% | 48% | R+4.0 | — | 0.1 | 1.5 | R+2.6 |
Jun 11-Jul 2 6/11-7/2 | SurveyMonkey | 428 | LV | 0.00 | 45% | 53% | R+7.6 | — | 0.8 | 1.0 | R+5.9 |
Jun 13-15 6/13-15 | Mason-Dixon Polling & Research, Inc. | 625 | RV | 0.00 | 44% | 48% | R+4.0 | 0.2 | 0.8 | 0.3 | R+3.1 |
Feb 21-24 2/21-24 | Gravis Marketing | 385 | RV | 0.00 | 43% | 40% | D+3.0 | 0.2 | 0.5 | 1.4 | D+4.7 |
Feb 18-20 2/18-20 | Tarrance Group R | 500 | LV | 0.00 | 44% | 49% | R+5.0 | — | 0.5 | 4.6 | D+0.1 |
Our state similarity scores are based on demographic, geographic and political characteristics; if two states 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 states, given what it says in similar states.
Sim. score | Polling avg. | ||
---|---|---|---|
South Dakota | 78 | — | |
Nebraska | 61 | R+15.5 | |
Kansas | 58 | — | |
Wyoming | 54 | R+29.6 | |
Montana | 52 | D+3.5 | |
Idaho | 49 | — | |
Iowa | 49 | — | |
Indiana | 46 | D+3.0 | |
Missouri | 45 | D+0.5 | |
Kentucky | 40 | No race |
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 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 midterm forecasts. Read more …
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