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Chance the Democrat wins (6.2%)
Chance the Republican wins (93.8%)
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+8.0
Adjusted polls
R+10.3
CANTOR
R+11.0
Fundamentals
R+20.0
Experts
R+9.1
Lite
R+9.8
Classic
R+13.2
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected two polls for the Michigan 2nd. 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 | Davidson | Huizenga | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 11-15 10/11-15 | Lake Research Partners D | 400 | LV | 0.91 | 42% | 48% | R+6.0 | — | <0.1 | 2.0 | R+8.0 |
Jul. 12-15 7/12-15 | Lake Research Partners D | 400 | LV | 0.00 | 28% | 50% | R+22.0 | — | 0.6 | 2.0 | R+23.3 |
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 | 81 | — | |
IN-2 | 80 | — | |
IN-9 | 75 | R+7.6 | |
IL-16 | 74 | R+14.6 | |
MI-6 | 74 | R+2.7 | |
KS-2 | 73 | D+0.1 | |
IL-13 | 73 | R+5.4 | |
IL-12 | 72 | R+6.9 | |
OH-2 | 70 | R+13.6 | |
MI-7 | 70 | R+6.6 |
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 | 3.1 | Bill Huizenga has been elected to 4 terms. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 6.2 | MI-2 is 17.7 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 | 11.9 | Huizenga won by 30.1 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 | 2.1 | As of Oct. 17, Rob Davidson had raised $948,000 in individual contributions (59% of all such contributions to the major-party candidates); Huizenga had raised $670,000 (41%). |
Incumbent's voting record in Congress | 2.1 | Huizenga has voted with Republicans 87% 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 | Davidson has never held elected office. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | R+11.0 |
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+24.5 | R+23.8 | |
Inside Elections | R+24.5 | R+23.6 | |
Sabato's Crystal Ball | R+12.1 | R+12.5 | |
Average | R+20.3 | R+20.0 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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