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Chance a Democrat* wins
Chance the Republican wins (0.9%)
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.
D+16.8
Adjusted polls
D+16.6
CANTOR
D+28.7
Fundamentals
D+23.1
Experts
D+16.8
Lite
D+19.9
Classic
D+21.0
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected five polls for the Maine 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 | King | Ringelstein | Brakey | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct 27-29 10/27-29 | Emerson College | 883 | LV | 2.34 | 50% | 6% | 37% | D+13.2 | — | <0.1 | 0.6 | D+13.8 |
Oct 8-16 10/8-16 | Critical Insights R | 600 | LV | 0.38 | 41% | 7% | 27% | D+14.0 | — | <0.1 | 5.2 | D+19.2 |
Oct 1-7 10/1-7 | Pan Atlantic SMS Group | 500 | LV | 0.39 | 57% | 8% | 30% | D+27.6 | — | <0.1 | 1.1 | D+26.5 |
Sep 27-30 9/27-30 | Self-Made Insights R | 750 | LV | 0.23 | 47% | 8% | 36% | D+11.0 | — | <0.1 | 6.5 | D+17.5 |
Aug 2-6 8/2-6 | Suffolk University | 500 | LV | 0.02 | 55% | 4% | 26% | D+29.1 | — | 0.6 | 0.3 | D+29.4 |
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. | ||
---|---|---|---|
Vermont | 68 | D+39.7 | |
New Hampshire | 62 | — | |
Wisconsin | 46 | D+12.2 | |
Michigan | 45 | D+10.7 | |
Pennsylvania | 45 | D+11.7 | |
Iowa | 42 | — | |
Minnesota | 39 | D+20.4 | |
Minnesota (special) | 39 | D+8.5 | |
Oregon | 35 | — | |
Ohio | 33 | 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 | D+22.7 | D+23.3 | |
Inside Elections | D+22.7 | D+23.6 | |
Sabato's Crystal Ball | D+22.7 | D+22.3 | |
Average | D+22.7 | D+23.1 |
Nate Silver explains the methodology behind our 2018 midterm forecasts. Read more …
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