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Chance the Democrat wins (0.2%)
Chance the Republican wins (99.8%)
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+13.7
Adjusted polls
R+21.5
CANTOR
R+25.4
Fundamentals
R+23.3
Experts
R+18.6
Lite
R+22.1
Classic
R+22.5
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected one poll for the Indiana 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 | Tritch | Banks | margin | likely voter | Time-line | House effects | Adjusted margin | |
May 29-31 5/29-31 | WPA Intelligence R | 401 | LV | 0.49 | 34% | 55% | R+21.0 | — | 0.8 | 6.5 | R+13.7 |
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. | ||
---|---|---|---|
IN-4 | 83 | — | |
OH-8 | 79 | — | |
IN-6 | 77 | — | |
OH-4 | 76 | R+24.6 | |
IN-9 | 74 | R+7.6 | |
OH-7 | 72 | R+12.2 | |
IN-8 | 72 | — | |
OH-5 | 70 | — | |
MO-4 | 70 | — | |
MO-6 | 69 | — |
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 | James Banks has been elected to 1 term. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 12.6 | IN-3 is 34.1 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 | 22.0 | Banks won by 47.1 percentage points in 2016 in an open-seat race. |
Generic ballot | 6.9 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 3.8 | As of Oct. 17, Courtney Tritch had raised $802,000 in individual contributions (65% of all such contributions to the major-party candidates); Banks had raised $429,000 (35%). |
Incumbent's voting record in Congress | 2.3 | Banks has voted with Republicans 88% 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 | Tritch has never held elected office. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | R+25.4 |
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+23.7 | R+23.1 | |
Inside Elections | R+23.7 | R+22.8 | |
Sabato's Crystal Ball | R+23.7 | R+24.1 | |
Average | R+23.7 | R+23.3 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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