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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+22.2
Adjusted polls
D+26.3
CANTOR
D+39.5
Fundamentals
D+29.2
Experts
D+22.2
Lite
D+28.6
Classic
D+28.8
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected five polls for the Rhode Island 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 | Whitehouse | Flanders | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct 20-24 10/20-24 | Fleming & Associates | 416 | LV | 1.17 | 55% | 36% | D+19.0 | — | <0.1 | 2.0 | D+21.0 |
Oct 5-9 10/5-9 | SocialSphere | 502 | RV | 0.49 | 56% | 32% | D+24.0 | 0.2 | <0.1 | 0.2 | D+23.5 |
Sep 27-Oct 6 9/27-10/6 | University of New Hampshire | 503 | LV | 0.46 | 57% | 33% | D+24.0 | — | <0.1 | 0.4 | D+23.6 |
Sep 14-17 9/14-17 | Fleming & Associates | 420 | LV | 0.05 | 54% | 35% | D+19.0 | — | 0.1 | 2.0 | D+20.9 |
May 30-Jun 4 5/30-6/4 | SocialSphere | 501 | RV | 0.00 | 54% | 32% | D+22.0 | 0.2 | 1.1 | 0.2 | D+22.6 |
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. | ||
---|---|---|---|
Massachusetts | 74 | D+23.2 | |
Connecticut | 62 | D+18.8 | |
New York | 60 | D+24.7 | |
New Jersey | 54 | D+10.1 | |
Delaware | 47 | D+20.8 | |
Illinois | 44 | — | |
Pennsylvania | 36 | D+11.7 | |
Maryland | 31 | D+33.6 | |
Vermont | 29 | D+39.7 | |
New Hampshire | 29 | — |
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+28.9 | D+29.5 | |
Inside Elections | D+28.9 | D+29.8 | |
Sabato's Crystal Ball | D+28.9 | D+28.5 | |
Average | D+28.9 | D+29.2 |
Nate Silver explains the methodology behind our 2018 midterm forecasts. Read more …
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