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Chance the Democrat wins (>99.9%)
Chance the Republican wins (<0.1%)
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+25.1
Adjusted polls
D+26.3
CANTOR
D+27.6
Fundamentals
D+27.1
Experts
D+25.2
Lite
D+26.1
Classic
D+26.4
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected two polls for the Maine 1st. 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 | Pingree | Holbrook | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 27-29 10/27-29 | Emerson College | 442 | LV | 1.38 | 56% | 31% | D+25.2 | — | <0.1 | 0.6 | D+25.8 |
Oct. 1-7 10/1-7 | Pan Atlantic SMS Group | 249 | LV | 0.38 | 53% | 29% | D+24.0 | — | <0.1 | 1.1 | D+22.9 |
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. | ||
---|---|---|---|
VT at large | 81 | D+38.9 | |
NH-2 | 67 | D+17.8 | |
CT-2 | 59 | — | |
MA-9 | 58 | — | |
NH-1 | 58 | D+7.2 | |
NY-24 | 57 | R+13.8 | |
NY-20 | 57 | — | |
NY-19 | 55 | D+1.5 | |
MA-2 | 52 | — | |
MA-1 | 48 | — |
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 | 3.0 | Chellie Pingree has been elected to 5 terms. Congress has only a 20.1% approval rating, reducing the incumbency advantage. |
District partisanship | 5.1 | ME-1 is 14.8 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. |
Incumbent's margin in last election | 6.7 | Pingree won by 16.0 percentage points in 2016. |
Generic ballot | 6.6 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 8.6 | As of Oct. 17, Pingree had raised $455,000 in individual contributions (86% of all such contributions to the major-party candidates); Mark Holbrook had raised $77,000 (14%). |
Incumbent's voting record in Congress | 3.2 | Pingree has voted with Democrats 93% 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 | Holbrook has never held elected office. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | D+27.6 |
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 | D+26.7 | D+27.3 | |
Inside Elections | D+26.7 | D+27.6 | |
Sabato's Crystal Ball | D+26.7 | D+26.3 | |
Average | D+26.7 | D+27.1 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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