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Chance the Democrat wins (99.9%)
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+20.8
Adjusted polls
D+19.4
CANTOR
D+36.0
Fundamentals
D+27.8
Experts
D+20.6
Lite
D+27.0
Classic
D+27.3
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected two polls for the Delaware 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 | Carper | Arlett | margin | likely voter | Time-line | House effects | Adjusted margin | |
Sep 11-17 9/11-17 | University of Delaware | 728 | LV | 1.14 | 61% | 24% | D+37.0 | — | 0.1 | 10.0 | D+26.9 |
Jul 24-29 7/24-29 | Gravis Marketing | 884 | LV | 0.53 | 47% | 39% | D+8.0 | — | 0.5 | 1.4 | D+9.9 |
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. | ||
---|---|---|---|
Maryland | 64 | D+33.6 | |
Illinois | 59 | — | |
Virginia | 58 | D+14.1 | |
Pennsylvania | 58 | D+11.7 | |
New York | 57 | D+24.7 | |
Connecticut | 53 | D+18.8 | |
Michigan | 52 | D+10.7 | |
New Jersey | 50 | D+10.1 | |
Rhode Island | 47 | D+22.2 | |
Minnesota | 44 | D+20.4 | |
Minnesota (special) | 44 | D+8.5 |
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+27.4 | D+28.1 | |
Inside Elections | D+27.4 | D+28.3 | |
Sabato's Crystal Ball | D+27.4 | D+27.0 | |
Average | D+27.4 | D+27.8 |
Nate Silver explains the methodology behind our 2018 midterm forecasts. Read more …
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