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Chance the Democrat wins (<0.1%)
Chance the Republican wins (>99.9%)
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+43.2
Adjusted polls
R+25.4
CANTOR
R+37.4
Fundamentals
R+37.9
Experts
R+33.1
Lite
R+38.3
Classic
R+38.1
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected three polls for the Utah 3rd. 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 | Singer | Curtis | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 3-9 10/3-9 | University of Utah | 143 | RV | 0.31 | 13% | 67% | R+54.0 | 0.2 | <0.1 | 1.1 | R+53.1 |
Aug. 22-31 8/22-31 | Dan Jones & Associates | 188 | LV | 0.13 | 19% | 65% | R+46.0 | — | 0.1 | 1.6 | R+44.3 |
Aug. 11-27 8/11-27 | Lighthouse Research | 600 | RV | 0.21 | 20% | 52% | R+31.8 | 0.2 | 0.3 | 0.5 | R+31.2 |
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. | ||
---|---|---|---|
UT-1 | 72 | R+33.3 | |
UT-2 | 52 | R+20.6 | |
UT-4 | 48 | D+2.5 | |
ID-2 | 36 | R+35.0 | |
CO-5 | 29 | — | |
CO-4 | 24 | — | |
AZ-5 | 21 | — | |
ID-1 | 16 | R+7.0 | |
WY at large | 15 | R+27.6 | |
GA-11 | 14 | — |
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 | 2.8 | John Curtis has been elected to 1 term. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 12.7 | UT-3 is 38.8 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 | 17.6 | Curtis won by 32.4 percentage points in a special election. |
Generic ballot | 6.0 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 10.6 | As of Oct. 17, Curtis had raised $982,000 in individual contributions (98% of all such contributions to the major-party candidates); James Singer had raised $17,000 (2%). |
Incumbent's voting record in Congress | 0.9 | Curtis has voted with Republicans 82% of the time in roll-call votes in recent sessions of Congress. |
Challenger experience | 0.6 | Singer has never held elected office. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | R+37.4 |
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+38.3 | R+37.6 | |
Inside Elections | R+38.3 | R+37.4 | |
Sabato's Crystal Ball | R+38.3 | R+38.7 | |
Average | R+38.3 | R+37.9 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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