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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+33.3
Adjusted polls
R+26.7
CANTOR
R+33.3
Fundamentals
R+32.5
Experts
R+29.6
Lite
R+32.9
Classic
R+32.7
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected three polls for the Utah 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 | Castillo | Bishop | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 3-9 10/3-9 | University of Utah | 143 | RV | 0.31 | 20% | 52% | R+32.0 | 0.2 | <0.1 | 1.1 | R+31.1 |
Aug. 22-31 8/22-31 | Dan Jones & Associates | 201 | LV | 0.14 | 22% | 59% | R+37.0 | — | <0.1 | 1.6 | R+35.3 |
Aug. 11-27 8/11-27 | Lighthouse Research | 600 | RV | 0.21 | 16% | 51% | R+35.2 | 0.2 | 0.3 | 0.5 | R+34.6 |
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-3 | 72 | R+43.2 | |
UT-2 | 66 | R+20.6 | |
UT-4 | 61 | D+2.5 | |
ID-2 | 57 | R+35.0 | |
ID-1 | 40 | R+7.0 | |
CO-5 | 39 | — | |
WY at large | 37 | R+27.6 | |
CO-4 | 33 | — | |
KS-4 | 27 | R+28.3 | |
NV-2 | 26 | R+19.3 |
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 | Rob Bishop has been elected to 8 terms. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 13.3 | UT-1 is 40.5 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 | 14.3 | Bishop won by 39.5 percentage points in 2016. |
Generic ballot | 6.0 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 10.3 | As of Oct. 17, Bishop had raised $595,000 in individual contributions (97% of all such contributions to the major-party candidates); Lee Castillo had raised $20,000 (3%). |
Incumbent's voting record in Congress | 1.8 | Bishop has voted with Republicans 87% 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 | 0.6 | Castillo has never held elected office. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | R+33.3 |
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 | R+32.9 | R+32.3 | |
Inside Elections | R+32.9 | R+32.0 | |
Sabato's Crystal Ball | R+32.9 | R+33.3 | |
Average | R+32.9 | R+32.5 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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