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Chance the Democrat wins (32.5%)
Chance the Republican wins (67.5%)
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+3.0
Adjusted polls
R+5.3
CANTOR
R+1.4
Fundamentals
R+4.1
Experts
R+3.0
Lite
R+2.6
Classic
R+3.1
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected four polls for the Pennsylvania 10th. 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 | Scott | Perry | margin | likely voter | Time-line | House effects | Adjusted margin | |
Oct. 23-26 10/23-26 | Siena College/New York Times | 498 | LV | 1.63 | 43% | 45% | R+1.6 | — | <0.1 | 0.3 | R+1.8 |
Oct. 19-21 10/19-21 | Susquehanna Polling & Research, Inc. | 366 | LV | 0.72 | 46% | 49% | R+3.0 | — | <0.1 | 2.4 | R+5.4 |
Sep. 24-25 9/24-25 | Public Policy Polling D | 650 | V | 0.27 | 43% | 44% | R+1.0 | 0.1 | 0.1 | 1.9 | R+3.1 |
Jun. 8-10 6/8-10 | Public Policy Polling D | 654 | LV | 0.00 | 41% | 45% | R+4.0 | — | 0.9 | 1.9 | R+5.0 |
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. | ||
---|---|---|---|
OH-10 | 70 | — | |
PA-7 | 69 | D+7.8 | |
WI-1 | 69 | R+2.7 | |
MI-3 | 66 | — | |
IL-13 | 65 | R+5.4 | |
OH-1 | 65 | R+6.3 | |
PA-17 | 62 | D+12.5 | |
MI-6 | 62 | R+2.7 | |
PA-11 | 61 | R+8.4 | |
MI-8 | 61 | D+2.6 |
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 | 0.1 | Scott Perry has been elected to 3 terms. Congress has only a 20.1% approval rating, reducing the incumbency advantage. Pennsylvania underwent redistricting and there is 59% overlap between Perry's old and new district. |
District partisanship | 3.9 | PA-10 is 10.7 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 | 9.8 | Perry won by 32.1 percentage points in 2016. However, Pennsylvania has since undergone redistricting. Perry's district is now considerably more Democratic. |
Generic ballot | 7.0 | Democrats lead by an average of 8.6 percentage points in polls of the generic congressional ballot. |
Fundraising | 4.3 | As of Oct. 17, George B. Scott had raised $1,425,000 in individual contributions (67% of all such contributions to the major-party candidates); Perry had raised $705,000 (33%). |
Incumbent's voting record in Congress | 1.8 | Perry has voted with Republicans 85% of the time in roll-call votes in recent sessions of Congress. |
Challenger experience | 0.7 | Scott has never held elected office. |
Scandals | 0.0 | Neither candidate is involved in a scandal. |
Total | R+1.4 |
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 | EVEN | D+0.6 | |
Inside Elections | R+6.7 | R+5.8 | |
Sabato's Crystal Ball | R+6.7 | R+7.1 | |
Average | R+4.5 | R+4.1 |
Nate Silver explains the methodology behind our 2018 midterms forecast. Read more …
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