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Chance the Democrat wins (24.3%)
Chance the Republican wins (75.7%)
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+4.6
Adjusted polls
R+13.0
CANTOR
R+2.2
Fundamentals
R+6.3
Experts
R+4.6
Lite
R+4.3
Classic
R+5.0
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected five polls for the New York 27th. 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 | McMurray | Collins | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 29-30 10/29-30 | Dixie Strategies | 801 | LV | 1.81 | 38% | 45% | R+7.2 | — | <0.1 | 1.1 | R+6.1 |
Oct. 24-29 10/24-29 | Siena College/New York Times | 501 | LV | 1.43 | 40% | 44% | R+4.4 | — | <0.1 | 0.3 | R+4.6 |
Oct. 25-28 10/25-28 | Tulchin Research D | 400 | LV | 0.74 | 47% | 43% | D+4.0 | — | <0.1 | 5.3 | R+1.3 |
Oct. 6-11 10/6-11 | Siena College | 490 | LV | 0.24 | 43% | 46% | R+3.0 | — | <0.1 | 0.3 | R+3.3 |
Oct. 6-8 10/6-8 | Tulchin Research D | 400 | LV | 0.10 | 42% | 42% | EVEN | — | <0.1 | 5.3 | R+5.3 |
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. | ||
---|---|---|---|
NY-22 | 70 | R+1.1 | |
PA-9 | 69 | R+23.4 | |
MI-10 | 68 | — | |
WI-6 | 65 | R+15.2 | |
PA-14 | 65 | — | |
PA-16 | 64 | R+3.1 | |
NY-23 | 64 | R+3.5 | |
NY-19 | 64 | D+1.5 | |
NH-1 | 63 | D+7.2 | |
OH-5 | 63 | — |
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 | Chris Collins has been elected to 3 terms. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 8.1 | NY-27 is 22.8 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 | 13.8 | Collins won by 34.4 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 | 4.4 | As of Oct. 17, Nate McMurray had raised $825,000 in individual contributions (68% of all such contributions to the major-party candidates); Collins had raised $391,000 (32%). |
Incumbent's voting record in Congress | 1.3 | Collins has voted with Republicans 83% of the time in roll-call votes in recent sessions of Congress. |
Challenger experience | 1.9 | McMurray has held elected office before. (So has Collins, but this is accounted for in our incumbency calculation.) |
Scandals | 8.3 | Collins is involved in a scandal that developed since the last election for this seat. |
Total | R+2.2 |
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+6.7 | R+5.8 | |
Sabato's Crystal Ball | R+6.7 | R+7.1 | |
Average | R+6.7 | R+6.3 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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