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Chance the Democrat wins (1.0%)
Chance the Republican wins (99.0%)
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+12.7
Adjusted polls
R+13.4
CANTOR
R+22.1
Fundamentals
R+21.9
Experts
R+13.1
Lite
R+18.2
Classic
R+19.5
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected one poll for the Oregon 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 | McLeod-Skinner | Walden | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 11-12 10/11-12 | Patinkin Research Strategies D | 400 | LV | 0.77 | 40% | 49% | R+9.0 | — | <0.1 | 3.7 | R+12.7 |
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. | ||
---|---|---|---|
CA-1 | 78 | — | |
CO-3 | 71 | R+9.0 | |
MT at large | 66 | R+4.6 | |
WA-3 | 66 | R+4.9 | |
WA-5 | 66 | R+6.9 | |
ID-2 | 62 | R+35.0 | |
ID-1 | 60 | R+7.0 | |
OR-4 | 58 | — | |
NV-2 | 54 | R+19.3 | |
CA-4 | 53 | R+6.5 |
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 | 3.0 | Greg Walden has been elected to 10 terms. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 7.4 | OR-2 is 21.5 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 | 17.7 | Walden won by 43.7 percentage points in 2016. |
Generic ballot | 6.6 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 3.5 | As of Oct. 17, Walden had raised $1,857,000 in individual contributions (64% of all such contributions to the major-party candidates); Jamie McLeod-Skinner had raised $1,033,000 (36%). |
Incumbent's voting record in Congress | 1.0 | Walden has voted with Republicans 82% of the time in roll-call votes in recent sessions of Congress. |
Challenger experience | 1.9 | McLeod-Skinner has held elected office before. (So has Walden, but this is accounted for in our incumbency calculation.) |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | R+22.1 |
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 | Raw | Adjusted |
Cook Political Report | R+22.3 | R+21.7 | |
Inside Elections | R+22.3 | R+21.4 | |
Sabato's Crystal Ball | R+22.3 | R+22.7 | |
Average | R+22.3 | R+21.9 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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