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Chance the Democrat wins (2.1%)
Chance the Republican wins (97.9%)
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+15.5
Adjusted polls
R+13.1
CANTOR
R+14.5
Fundamentals
R+22.4
Experts
R+14.4
Lite
R+14.8
Classic
R+17.4
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected three polls for the Nebraska 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 | Raybould | Fischer | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct 23-27 10/23-27 | DFM Research D | 683 | LV | 0.83 | 39% | 54% | R+15.0 | — | <0.1 | 1.6 | R+16.6 |
Jan 24-28 1/24-28 | Meeting Street Research R | 500 | LV | 0.10 | 34% | 51% | R+17.0 | — | 0.2 | 3.4 | R+13.4 |
Nov 10-12 11/10-12 | Public Policy Polling D | 1,190 | V | 0.11 | 31% | 42% | R+11.0 | 0.1 | 0.4 | 1.9 | R+13.4 |
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. | ||
---|---|---|---|
Kansas | 80 | — | |
South Dakota | 70 | — | |
Indiana | 66 | D+3.0 | |
Iowa | 64 | — | |
North Dakota | 61 | R+8.6 | |
Missouri | 59 | D+0.5 | |
Wisconsin | 59 | D+12.2 | |
Minnesota | 55 | D+20.4 | |
Minnesota (special) | 55 | D+8.5 | |
Ohio | 54 | D+11.9 |
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 Rating | Raw | Adjusted |
Cook Political Report | R+22.8 | R+22.1 | |
Inside Elections | R+22.8 | R+21.9 | |
Sabato's Crystal Ball | R+22.8 | R+23.2 | |
Average | R+22.8 | R+22.4 |
Nate Silver explains the methodology behind our 2018 midterm forecasts. Read more …
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