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Chance the Democrat wins (99.7%)
Chance the Republican wins (0.3%)
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+18.8
Adjusted polls
D+17.5
CANTOR
D+33.1
Fundamentals
D+23.7
Experts
D+18.8
Lite
D+21.3
Classic
D+22.1
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected six polls for the Connecticut 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 | Murphy | Corey | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct 30-Nov 1 10/30-11/1 | Gravis Marketing | 681 | LV | 1.51 | 58% | 35% | D+23.0 | — | <0.1 | 1.4 | D+24.4 |
Oct 27-29 10/27-29 | Emerson College | 780 | LV | 1.93 | 55% | 35% | D+20.0 | — | <0.1 | 0.6 | D+20.6 |
Oct 22-28 10/22-28 | Quinnipiac University | 1,201 | LV | 2.08 | 56% | 41% | D+15.0 | — | <0.1 | 1.0 | D+14.1 |
Oct 3-8 10/3-8 | Quinnipiac University | 767 | LV | 0.21 | 57% | 42% | D+15.0 | — | <0.1 | 1.0 | D+14.0 |
Aug 24-27 8/24-27 | Gravis Marketing | 606 | LV | 0.00 | 54% | 37% | D+17.0 | — | 0.1 | 1.4 | D+18.5 |
Aug 16-21 8/16-21 | Quinnipiac University | 1,029 | RV | 0.00 | 59% | 31% | D+28.0 | 0.2 | 0.3 | 1.0 | D+27.1 |
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. | ||
---|---|---|---|
New Jersey | 79 | D+10.1 | |
Massachusetts | 70 | D+23.2 | |
New York | 67 | D+24.7 | |
Rhode Island | 62 | D+22.2 | |
Illinois | 60 | — | |
Maryland | 55 | D+33.6 | |
Delaware | 53 | D+20.8 | |
Pennsylvania | 51 | D+11.7 | |
New Hampshire | 49 | — | |
Virginia | 44 | D+14.1 |
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+23.3 | D+23.9 | |
Inside Elections | D+23.3 | D+24.2 | |
Sabato's Crystal Ball | D+23.3 | D+22.9 | |
Average | D+23.3 | D+23.7 |
Nate Silver explains the methodology behind our 2018 midterm forecasts. Read more …
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