Get more FiveThirtyEight
- Terms of Use
- Privacy Policy
- Your California Privacy Rights
- Children's Online Privacy Policy
- Interest-Based Ads
© 2018 ABC News Internet Ventures. All rights reserved.
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+18.6
Adjusted polls
R+30.7
CANTOR
R+41.9
Fundamentals
R+28.4
Experts
R+19.9
Lite
R+28.5
Classic
R+28.4
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected five polls for the Kansas 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 | LaPolice | Marshall | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 26-28 10/26-28 | Emerson College | 221 | LV | 0.74 | 36% | 51% | R+14.9 | — | <0.1 | 0.6 | R+14.3 |
Oct. 22-23 10/22-23 | Jayhawk Consulting D | 600 | LV | 0.53 | 38% | 42% | R+4.0 | — | <0.1 | 9.6 | R+13.6 |
Oct. 8-9 10/8-9 | Remington Research Group R | 1,432 | LV | 0.46 | 26% | 60% | R+34.0 | — | <0.1 | 5.6 | R+28.4 |
Sep. 26-28 9/26-28 | Emerson College | 193 | RV | 0.03 | 17% | 44% | R+26.6 | 0.2 | <0.1 | 0.6 | R+26.2 |
Sep. 21-22 9/21-22 | Jayhawk Consulting D | 400 | LV | 0.02 | 33% | 44% | R+11.0 | — | 0.1 | 9.6 | R+20.7 |
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. | ||
---|---|---|---|
NE-3 | 70 | — | |
ND at large | 65 | R+19.7 | |
IL-15 | 63 | — | |
MO-4 | 62 | — | |
SD at large | 62 | R+15.0 | |
TN-4 | 61 | — | |
IN-4 | 60 | — | |
MO-3 | 60 | — | |
IN-3 | 60 | R+13.7 | |
MO-7 | 60 | — |
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 | 3.1 | Roger Marshall has been elected to 1 term. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 17.3 | KS-1 is 46.6 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 | 25.6 | Marshall won by 39.6 percentage points in 2016 in an open-seat race, but did not face major-party opposition. |
Generic ballot | 6.7 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 3.5 | As of Oct. 17, Marshall had raised $363,000 in individual contributions (64% of all such contributions to the major-party candidates); Alan LaPolice had raised $201,000 (36%). |
Incumbent's voting record in Congress | 1.5 | Marshall has voted with Republicans 84% of the time in roll-call votes in recent sessions of Congress. |
Challenger experience | 0.7 | LaPolice has never held elected office. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | R+41.9 |
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+28.8 | R+28.1 | |
Inside Elections | R+28.8 | R+27.9 | |
Sabato's Crystal Ball | R+28.8 | R+29.1 | |
Average | R+28.8 | R+28.4 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
Comments