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Chance the Democrat wins (22.5%)
Chance the Republican wins (77.5%)
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+2.7
Adjusted polls
R+3.2
CANTOR
R+7.6
Fundamentals
R+8.1
Experts
R+2.8
Lite
R+4.8
Classic
R+5.9
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected five polls for the Michigan 6th. 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 | Longjohn | Upton | margin | likely voter | Time-line | House effects | Adjusted margin | |
Nov. 2-4 11/2-4 | Change Research D | 460 | LV | 0.70 | 42% | 40% | D+2.0 | — | <0.1 | 1.5 | D+0.5 |
Oct. 27-29 10/27-29 | Change Research | 466 | LV | 0.50 | 43% | 46% | R+3.0 | — | <0.1 | 0.6 | R+3.6 |
Oct. 9-10 10/9-10 | DCCC Targeting Team D | 605 | LV | 0.27 | 46% | 49% | R+3.0 | — | <0.1 | 2.9 | R+6.0 |
Sep. 4-5 9/4-5 | Public Policy Polling D | 750 | V | 0.06 | 41% | 45% | R+4.0 | 0.1 | 0.1 | 1.9 | R+6.1 |
Aug. 24-29 8/24-29 | Global Strategy Group D | 500 | LV | 0.03 | 44% | 49% | R+5.0 | — | 0.1 | 1.9 | R+6.9 |
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. | ||
---|---|---|---|
MI-3 | 78 | — | |
MI-7 | 77 | R+6.6 | |
IA-2 | 77 | D+13.3 | |
MI-2 | 74 | R+8.0 | |
IL-13 | 71 | R+5.4 | |
IN-9 | 70 | R+7.6 | |
OH-15 | 69 | — | |
IL-12 | 68 | R+6.9 | |
PA-16 | 68 | R+3.1 | |
IA-1 | 67 | D+8.8 |
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 | Fred Upton has been elected to 16 terms. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 2.7 | MI-6 is 7.7 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 | 8.6 | Upton won by 22.2 percentage points in 2016. |
Generic ballot | 6.8 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 0.3 | As of Oct. 17, Matt Longjohn had raised $1,146,000 in individual contributions (51% of all such contributions to the major-party candidates); Upton had raised $1,100,000 (49%). |
Incumbent's voting record in Congress | 0.4 | Upton has voted with Republicans 79% of the time in roll-call votes in recent sessions of Congress. |
Challenger experience | 0.7 | Longjohn has never held elected office. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | R+7.6 |
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 | R+6.7 | R+6.1 | |
Inside Elections | R+12.1 | R+11.2 | |
Sabato's Crystal Ball | R+6.7 | R+7.1 | |
Average | R+8.5 | R+8.1 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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