Get more FiveThirtyEight
- Terms of Use
- Privacy Policy
- Your California Privacy Rights
- Children's Online Privacy Policy
- Interest-Based Ads
© 2018 ABC News Internet Ventures. All rights reserved.
Chance the Democrat wins (1.4%)
Chance the Republican wins (98.6%)
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.
R+14.9
Adjusted polls
R+8.2
CANTOR
R+18.5
Fundamentals
R+22.1
Experts
R+14.9
Lite
R+15.8
Classic
R+17.9
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected five polls for Mississippi's regular 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 | Baria | Wicker | margin | likely voter | Time-line | House effects | Adjusted margin | |
Nov 2-4 11/2-4 | Change Research | 1,003 | LV | 1.88 | 40% | 48% | R+8.0 | — | <0.1 | 0.6 | R+8.6 |
Oct 13-18 10/13-18 | Marist College | 511 | LV | 0.72 | 32% | 59% | R+27.0 | — | <0.1 | 0.5 | R+27.5 |
Sep 9-24 9/9-24 | SurveyMonkey | 985 | RV | 0.09 | 29% | 43% | R+14.0 | 0.2 | 0.1 | 1.0 | R+13.3 |
Jul 30-31 7/30-31 | Triumph Campaigns | 2,100 | LV | 0.03 | 32% | 53% | R+20.8 | — | 0.5 | 4.0 | R+16.3 |
Apr 10-11 4/10-11 | Triumph Campaigns | 1,000 | LV | 0.00 | 31% | 48% | R+16.8 | — | 0.9 | 4.0 | R+11.9 |
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. | ||
---|---|---|---|
Mississippi (special) | 100 | R+17.0 | |
Alabama | 70 | — | |
Louisiana | 70 | No race | |
Arkansas | 68 | — | |
South Carolina | 64 | — | |
Georgia | 54 | — | |
Tennessee | 54 | R+4.7 | |
North Carolina | 52 | No race | |
Kentucky | 52 | No race | |
Oklahoma | 51 | — |
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 | R+22.5 | R+21.9 | |
Inside Elections | R+22.5 | R+21.6 | |
Sabato's Crystal Ball | R+22.5 | R+22.9 | |
Average | R+22.5 | R+22.1 |
Nate Silver explains the methodology behind our 2018 midterm forecasts. Read more …
Comments