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Chance the Democrat wins (34.7%)
Chance the Republican wins (65.3%)
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+3.1
Adjusted polls
R+6.9
CANTOR
R+0.6
Fundamentals
R+1.9
Experts
R+3.6
Lite
R+2.3
Classic
R+2.1
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected three polls for the Ohio 12th. 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 | O'Connor | Balderson | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 20-22 10/20-22 | GBA Strategies D | 570 | LV | 1.07 | 47% | 47% | EVEN | — | <0.1 | 2.1 | R+2.1 |
Oct. 11-13 10/11-13 | Clarity Campaign Labs D | 639 | LV | 0.67 | 46% | 48% | R+2.0 | — | <0.1 | 2.5 | R+4.6 |
Sep. 4-6 9/4-6 | GBA Strategies D | 500 | LV | 0.02 | 46% | 47% | R+1.0 | — | 0.1 | 2.1 | R+3.2 |
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. | ||
---|---|---|---|
IN-5 | 83 | R+6.6 | |
MI-8 | 80 | D+2.6 | |
OH-2 | 75 | R+13.6 | |
OH-15 | 72 | — | |
OH-14 | 69 | — | |
MN-2 | 68 | D+6.1 | |
IA-3 | 68 | D+1.6 | |
IL-14 | 67 | D+4.1 | |
OH-16 | 66 | R+5.1 | |
MI-3 | 66 | — |
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 | Troy Balderson has been elected to 1 term. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 4.9 | OH-12 is 14.0 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 | 5.2 | Balderson won by 0.8 percentage points in a special election. |
Generic ballot | 6.8 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 6.6 | As of Oct. 17, Danny O'Connor had raised $3,241,000 in individual contributions (76% of all such contributions to the major-party candidates); Balderson had raised $1,006,000 (24%). |
Incumbent's voting record in Congress | 2.6 | Balderson has voted with Republicans 65% of the time in roll-call votes in recent sessions of Congress. Candidates who break with their party more often tend to overperform at the ballot booth, other factors held equal. |
Challenger experience | 2.0 | O'Connor has held elected office before. (So has Balderson, but this is accounted for in our incumbency calculation.) |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | R+0.6 |
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 | EVEN | D+0.6 | |
Inside Elections | EVEN | D+0.9 | |
Sabato's Crystal Ball | R+6.7 | R+7.1 | |
Average | R+2.2 | R+1.9 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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