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Chance the Democrat wins (99.0%)
Chance the Republican wins (1.0%)
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.
D+12.8
Adjusted polls
D+17.4
CANTOR
D+26.7
Fundamentals
D+22.7
Experts
D+12.8
Lite
D+17.5
Classic
D+19.2
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected three polls for the New York 25th. 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 | Morelle | Maxwell | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 29-30 10/29-30 | Dixie Strategies | 843 | LV | 1.80 | 49% | 40% | D+9.1 | — | <0.1 | 1.1 | D+10.3 |
Oct. 4-8 10/4-8 | Siena College | 465 | LV | 0.66 | 53% | 36% | D+17.0 | — | <0.1 | 0.3 | D+16.7 |
Aug. 15-19 8/15-19 | Siena College | 500 | LV | 0.05 | 55% | 31% | D+24.0 | — | 0.3 | 0.3 | D+24.1 |
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-20 | 73 | — | |
NY-26 | 68 | — | |
PA-18 | 66 | — | |
CT-3 | 66 | — | |
NJ-1 | 66 | — | |
CT-1 | 65 | — | |
DE at large | 64 | D+16.3 | |
NY-24 | 61 | R+13.8 | |
MI-9 | 60 | — | |
MA-2 | 60 | — |
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 |
---|---|---|
District partisanship | 12.3 | NY-25 is 15.0 percentage points more Democratic-leaning than the country overall, based on how it has voted in recent presidential and state legislative elections. It voted for Clinton in 2016 and Obama in 2012. |
Previous incumbent's margin in last election | 0.8 | A Democrat won by 12.4 percentage points in this district in 2016. Previous district results are not strongly predictive in races without incumbents. |
Generic ballot | 8.5 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 2.6 | As of Oct. 17, Joseph Morelle had raised $893,000 in individual contributions (67% of all such contributions to the major-party candidates); Jim Maxwell had raised $434,000 (33%). |
Candidate experience | 2.5 | Morelle has held elected office before but Maxwell hasn't. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | D+26.7 |
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 | D+22.3 | D+22.9 | |
Inside Elections | D+22.3 | D+23.2 | |
Sabato's Crystal Ball | D+22.3 | D+21.9 | |
Average | D+22.3 | D+22.7 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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