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Chance the Democrat wins (16.2%)
Chance the Republican wins (83.8%)
We'll be updating our forecasts every time new data is available, every day through Nov. 6.
The Classic version of our model projects a race’s outcome by taking a weighted average of polls of a district (if available), polls of similar districts (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+4.8
Adjusted polls
R+7.9
CANTOR
R+7.3
Fundamentals
R+13.9
Experts
R+5.6
Lite
R+6.1
Classic
R+8.7
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected two polls for the Missouri 2nd. 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 | VanOstran | Wagner | margin | likely voter | Time-line | House effects | Adjusted margin | |
Aug. 23-26 8/23-26 | Expedition Strategies D | 402 | LV | 0.58 | 43% | 41% | D+2.0 | — | 0.1 | 4.2 | R+2.2 |
Aug. 22-23 8/22-23 | Remington Research Group | 983 | LV | 0.93 | 40% | 51% | R+11.0 | — | 0.1 | 4.3 | R+6.5 |
Key
A = adults
RV = Registered voters
V = voters
LV = likely voters
= partisan poll
Our district similarity scores are based on demographic, geographic and political characteristics; if two districts 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 districts, given what it says in similar districts.
Sim. score | Polling avg. | ||
---|---|---|---|
MI-11 | 65 | D+4.6 | |
NJ-4 | 57 | — | |
PA-17 | 56 | D+12.5 | |
OH-16 | 56 | R+5.1 | |
PA-1 | 56 | D+0.5 | |
IL-14 | 55 | D+4.1 | |
IN-5 | 55 | R+6.6 | |
KS-3 | 52 | D+9.8 | |
MN-3 | 52 | D+7.1 | |
IL-6 | 50 | D+1.0 |
The Classic and Deluxe versions of our model use several non-polling factors to forecast the vote share margin in each district.
Factor | Impact | Explanation |
---|---|---|
Incumbency | 3.1 | Ann Wagner has been elected to 3 terms. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 5.5 | MO-2 is 15.6 percentage points more Republican-leaning than the country overall, based on how it has voted in recent presidential and state legislative elections. It voted for Trump in 2016 and Romney in 2012. |
Incumbent's margin in last election | 8.0 | Wagner won by 20.9 percentage points in 2016. |
Generic ballot | 6.8 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 1.2 | As of Oct. 17, Cort VanOstran had raised $1,778,000 in individual contributions (55% of all such contributions to the major-party candidates); Wagner had raised $1,461,000 (45%). |
Incumbent's voting record in Congress | 1.9 | Wagner has voted with Republicans 86% of the time in roll-call votes in recent sessions of Congress. Candidates who vote with their party very frequently tend to underperform at the ballot booth, other factors held equal. |
Challenger experience | 0.7 | VanOstran has never held elected office. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | R+7.3 |
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 | Raw | Adjusted |
Cook Political Report | R+6.7 | R+6.1 | |
Inside Elections | R+24.0 | R+23.1 | |
Sabato's Crystal Ball | R+12.1 | R+12.5 | |
Average | R+14.3 | R+13.9 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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