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Chance the Democrat wins (0.6%)
Chance the Republican wins (99.4%)
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+7.0
Adjusted polls
R+19.2
CANTOR
R+32.6
Fundamentals
R+27.2
Experts
R+16.0
Lite
R+27.1
Classic
R+27.1
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected one poll for the Idaho 1st. 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 | McNeil | Fulcher | margin | likely voter | Time-line | House effects | Adjusted margin | |
Jun. 22-Jul. 9 6/22-7/9 | Dan Jones & Associates | 315 | A | 0.29 | 27% | 35% | R+8.0 | 1.4 | 0.8 | 1.6 | R+7.0 |
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. | ||
---|---|---|---|
WY at large | 70 | R+27.6 | |
ID-2 | 69 | R+35.0 | |
CA-1 | 64 | — | |
WA-5 | 62 | R+6.9 | |
AZ-4 | 61 | R+30.5 | |
OR-2 | 60 | R+12.7 | |
CO-4 | 56 | — | |
MT at large | 56 | R+4.6 | |
WA-3 | 56 | R+4.9 | |
IN-4 | 54 | — |
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 |
---|---|---|
District partisanship | 29.5 | ID-1 is 39.6 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. |
Previous incumbent's margin in last election | 2.0 | A Republican won by 36.4 percentage points in this district in 2016. Previous district results are not strongly predictive in races without incumbents. |
Generic ballot | 7.4 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 6.3 | As of Oct. 17, Russ Fulcher had raised $596,000 in individual contributions (98% of all such contributions to the major-party candidates); Cristina McNeil had raised $15,000 (2%). |
Candidate experience | 2.2 | Fulcher has held elected office before but McNeil hasn't. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | R+32.6 |
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+27.5 | R+26.9 | |
Inside Elections | R+27.5 | R+26.6 | |
Sabato's Crystal Ball | R+27.5 | R+27.9 | |
Average | R+27.5 | R+27.2 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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