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Chance the Democrat wins (3.8%)
Chance the Republican wins (96.2%)
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+12.2
Adjusted polls
R+15.8
CANTOR
R+9.5
Fundamentals
R+19.7
Experts
R+12.2
Lite
R+11.4
Classic
R+14.2
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected three polls for the Ohio 7th. 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 | Harbaugh | Gibbs | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 31-Nov. 1 10/31-11/1 | Optimus | 800 | LV | 1.39 | 36% | 55% | R+18.3 | — | <0.1 | 2.6 | R+15.6 |
Oct. 25-26 10/25-26 | Change Research D | 682 | LV | 0.80 | 43% | 49% | R+6.0 | — | <0.1 | 1.5 | R+7.5 |
Oct. 3-6 10/3-6 | Mellman Group D | 400 | LV | 0.22 | 38% | 45% | R+7.0 | — | <0.1 | 3.0 | R+10.0 |
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. | ||
---|---|---|---|
OH-5 | 84 | — | |
OH-4 | 84 | R+24.6 | |
IN-8 | 84 | — | |
IN-6 | 78 | — | |
PA-9 | 78 | R+23.4 | |
MI-10 | 75 | — | |
PA-14 | 74 | — | |
IL-16 | 73 | R+14.6 | |
IN-3 | 72 | R+13.7 | |
IN-9 | 72 | R+7.6 |
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 | Bob Gibbs has been elected to 4 terms. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 9.5 | OH-7 is 25.9 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 | 14.5 | Gibbs won by 35.1 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 | 9.7 | As of Oct. 17, Ken Harbaugh had raised $2,230,000 in individual contributions (88% of all such contributions to the major-party candidates); Gibbs had raised $308,000 (12%). |
Incumbent's voting record in Congress | 1.8 | Gibbs has voted with Republicans 85% 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 | Harbaugh has never held elected office. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | R+9.5 |
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+24.1 | R+23.5 | |
Inside Elections | R+24.1 | R+23.2 | |
Sabato's Crystal Ball | R+12.1 | R+12.5 | |
Average | R+20.1 | R+19.7 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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