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Chance the Democrat* wins
Chance the Republican wins (<0.1%)
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+39.7
Adjusted polls
D+27.4
CANTOR
D+45.9
Fundamentals
D+41.7
Experts
D+39.7
Lite
D+41.3
Classic
D+41.4
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected three polls for the Vermont 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 | Sanders | Zupan | margin | likely voter | Time-line | House effects | Adjusted margin | ||
Oct 30-Nov 1 10/30-11/1 | Gravis Marketing | 885 | LV | 1.72 | 66% | 30% | D+36.0 | — | <0.1 | 1.4 | D+37.4 | |
Oct 5-14 10/5-14 | Braun Research | 495 | LV | 0.47 | 60% | 19% | D+41.0 | — | <0.1 | 0.9 | D+41.9 | |
Sep 23-26 9/23-26 | Tulchin Research D | 406 | LV | 0.17 | 75% | 20% | D+55.0 | — | 0.1 | 5.3 | D+49.6 |
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. | ||
---|---|---|---|
Maine | 68 | D+16.8 | |
New Hampshire | 54 | — | |
Rhode Island | 29 | D+22.2 | |
Connecticut | 29 | D+18.8 | |
New York | 28 | D+24.7 | |
Massachusetts | 27 | D+23.2 | |
Wisconsin | 27 | D+12.2 | |
Minnesota (special) | 25 | D+8.5 | |
Minnesota | 25 | D+20.4 | |
Pennsylvania | 25 | D+11.7 |
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 Rating | Raw | Adjusted |
Cook Political Report | D+41.3 | D+41.9 | |
Inside Elections | D+41.3 | D+42.2 | |
Sabato's Crystal Ball | D+41.3 | D+40.9 | |
Average | D+41.3 | D+41.7 |
Nate Silver explains the methodology behind our 2018 midterm forecasts. Read more …
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