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Chance the Democrat wins (98.7%)
Chance the Republican wins (1.3%)
The Classic version of our model projects a race’s outcome by taking a weighted average of polls of the race (if available), polls of similar races (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+14.1
Adjusted polls
D+12.1
CANTOR
D+20.1
Fundamentals
D+22.9
Experts
D+14.1
Lite
D+15.8
Classic
D+18.2
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected seven polls for the Virginia Senate election. 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 | Kaine | Stewart | margin | likely voter | Time-line | House effects | Adjusted margin | |
Sep 4-9 9/4-9 | CNN/SSRS | 512 | LV | 1.04 | 52% | 36% | D+16.0 | — | 0.1 ![]() | 0.8 ![]() | D+15.1 |
Aug 22-24 8/22-24 | Cygnal | 1,119 | LV | 0.92 | 50% | 46% | D+4.5 | — | ![]() | ![]() | D+8.2 |
Aug 12-19 8/12-19 | Roanoke College | 512 | LV | 0.35 | 51% | 34% | D+17.0 | — | ![]() | ![]() | D+18.6 |
Jul 10-30 7/10-30 | Virginia Commonwealth University | 747 | LV | 0.26 | 49% | 26% | D+23.0 | — | ![]() | 2.4 ![]() | D+21.1 |
Jun 21-25 6/21-25 | Quinnipiac University | 1,153 | RV | 0.18 | 54% | 36% | D+18.0 | 0.2 ![]() | ![]() | 1.0 ![]() | D+17.6 |
May 20-30 5/20-30 | Roanoke College | 555 | RV | 0.00 | 44% | 33% | D+11.0 | 0.2 ![]() | ![]() | ![]() | D+13.0 |
Feb 5-28 2/5-28 | Christopher Newport University | 1,562 | RV | 0.01 | 56% | 32% | D+24.0 | 0.2 ![]() | ![]() | 1.6 ![]() | D+22.7 |
Our state similarity scores are based on demographic, geographic and political characteristics; if two states 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 states, given what it says in similar states.
Sim. score | Polling avg. | ||
---|---|---|---|
North Carolina | 68 | No race | |
Delaware | 58 | D+20.8 | |
Georgia | 58 | — | |
Pennsylvania | 58 | D+11.7 | |
Ohio | 55 | D+11.9 | |
Minnesota (special) | 54 | D+8.5 | |
Minnesota | 54 | D+20.4 | |
Illinois | 54 | — | |
Michigan | 52 | D+10.7 | |
Maryland | 52 | D+33.6 |
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 Rating | Raw | Adjusted |
Cook Political Report | D+22.5 | D+23.1 | |
Inside Elections | D+22.5 | D+23.4 | |
Sabato's Crystal Ball | D+22.5 | D+22.1 | |
Average | D+22.5 | D+22.9 |
Nate Silver explains the methodology behind our 2018 midterm forecasts. Read more …
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