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Chance a Democrat wins (25.2%)
Chance a Republican wins (74.8%)
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+17.0
Adjusted polls
R+2.6
CANTOR
R+8.3
Fundamentals
R+13.6
Experts
R+17.0
Lite
R+13.7
Classic
R+13.7
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected nine polls for Mississippi's special 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 | Espy | Hyde-Smith | McDaniel | margin | likely voter | Time-line | House effects | Adjusted margin | |
Nov 2-4 11/2-4 | Change Research | 1,003 | LV | 1.87 | 40% | 27% | 28% | D+13.0 | — | <0.1 | 0.6 | D+12.4 |
Oct 13-18 10/13-18 | Marist College | 511 | LV | 0.66 | 29% | 38% | 15% | R+9.0 | — | <0.1 | 0.5 | R+9.6 |
Sep 9-24 9/9-24 | SurveyMonkey | 985 | RV | 0.08 | 25% | 24% | 19% | D+1.0 | 0.5 | 0.1 | 1.0 | D+1.7 |
Aug 22-30 8/22-30 | Neighborhood Research Corporation R | 304 | LV | 0.02 | 28% | 27% | 18% | D+0.8 | — | 0.1 | 1.3 | D+4.6 |
Aug 1-7 8/1-7 | Mellman Group D | 600 | LV | 0.01 | 27% | 29% | 17% | R+2.0 | — | 0.5 | 3.0 | R+3.5 |
Jul 30-31 7/30-31 | Triumph Campaigns | 2,100 | LV | 0.02 | 27% | 41% | 15% | R+14.3 | — | 0.5 | 4.0 | R+10.5 |
May 1-3 5/1-3 | GS Strategy Group R | 500 | LV | 0.00 | 22% | 30% | 17% | R+8.0 | — | 1.0 | 3.7 | R+0.5 |
Apr 10-11 4/10-11 | Triumph Campaigns | 1,000 | LV | 0.00 | 33% | 33% | 13% | D+0.1 | — | 0.9 | 4.0 | D+4.5 |
Mar 27 3/27 | Chism Strategies D | 603 | LV | 0.00 | 34% | 27% | 21% | D+7.0 | — | 0.8 | 5.5 | D+3.9 |
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 | 100 | R+14.9 | |
Alabama | 70 | — | |
Arkansas | 68 | — | |
South Carolina | 64 | — | |
Georgia | 54 | — | |
Tennessee | 54 | R+4.7 | |
Oklahoma | 51 | — | |
Missouri | 44 | D+0.5 | |
West Virginia | 43 | D+7.7 | |
Indiana | 36 | D+3.0 |
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+6.7 | R+6.1 | |
Inside Elections | R+23.2 | R+22.3 | |
Sabato's Crystal Ball | R+12.1 | R+12.5 | |
Average | R+14.0 | R+13.6 |
Nate Silver explains the methodology behind our 2018 midterm forecasts. Read more …
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