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Chance the Democrat wins (9.2%)
Chance the Republican wins (90.8%)
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+14.3
Adjusted polls
R+10.1
CANTOR
R+3.9
Fundamentals
R+15.8
Experts
R+13.1
Lite
R+9.4
Classic
R+11.6
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected one poll for the Arizona 6th. 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 | Malik | Schweikert | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 11-15 10/11-15 | Siena College/New York Times | 500 | LV | 1.44 | 36% | 50% | R+14.0 | — | <0.1 | 0.3 | R+14.3 |
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. | ||
---|---|---|---|
AZ-8 | 67 | R+6.3 | |
AZ-5 | 67 | — | |
CA-50 | 59 | R+4.7 | |
CA-49 | 57 | D+9.8 | |
CA-48 | 56 | R+1.5 | |
CO-6 | 54 | D+8.4 | |
NV-3 | 53 | D+9.4 | |
CA-4 | 52 | R+6.5 | |
TX-21 | 51 | R+6.1 | |
KS-3 | 51 | D+9.8 |
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 | 3.2 | David Schweikert has been elected to 4 terms. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 6.3 | AZ-6 is 17.5 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 | 9.7 | Schweikert won by 24.3 percentage points in 2016. |
Generic ballot | 7.0 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 1.4 | As of Oct. 17, Schweikert had raised $421,000 in individual contributions (56% of all such contributions to the major-party candidates); Anita Malik had raised $336,000 (44%). |
Incumbent's voting record in Congress | 1.9 | Schweikert 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 | Malik has never held elected office. |
Scandals | 8.6 | Schweikert is involved in a scandal that developed since the last election for this seat. |
Total | R+3.9 |
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+12.1 | R+11.4 | |
Inside Elections | R+24.5 | R+23.6 | |
Sabato's Crystal Ball | R+12.1 | R+12.5 | |
Average | R+16.2 | R+15.8 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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