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Chance the Democrat wins (85.6%)
Chance the Republican wins (14.4%)
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+20.8
Adjusted polls
D+16.5
CANTOR
D+25.3
Fundamentals
D+24.7
Experts
D+0.4
Lite
D+10.5
Classic
D+15.3
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected one poll for the Oregon 5th. 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 | Schrader | Callahan | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 8 10/8 | Gravis Marketing R | 359 | LV | 0.63 | 33% | 56% | R+23.0 | — | <0.1 | 2.3 | R+20.8 |
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. | ||
---|---|---|---|
WA-6 | 72 | — | |
WA-3 | 71 | R+4.9 | |
WA-8 | 69 | D+0.5 | |
OR-4 | 68 | — | |
WA-10 | 67 | — | |
OR-1 | 63 | — | |
WA-5 | 61 | R+6.9 | |
WA-2 | 59 | — | |
AZ-2 | 59 | D+10.6 | |
WA-1 | 58 | — |
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 | Kurt Schrader has been elected to 5 terms. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 0.4 | OR-5 is 1.3 percentage points more Democratic-leaning than the country overall, based on how it has voted in recent presidential and state legislative elections. It voted for Clinton in 2016 and Obama in 2012. |
Incumbent's margin in last election | 4.5 | Schrader won by 10.5 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 | 11.1 | As of Oct. 17, Schrader had raised $576,000 in individual contributions (96% of all such contributions to the major-party candidates); Mark Callahan had raised $22,000 (4%). |
Incumbent's voting record in Congress | 1.0 | Schrader has voted with Democrats 82% of the time in roll-call votes in recent sessions of Congress. |
Challenger experience | 0.7 | Callahan has never held elected office. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | D+25.3 |
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 | D+24.3 | D+25.0 | |
Inside Elections | D+24.3 | D+25.2 | |
Sabato's Crystal Ball | D+24.3 | D+24.0 | |
Average | D+24.3 | D+24.7 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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