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Chance the Democrat wins (99.8%)
Chance the Republican wins (0.2%)
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+20.4
Adjusted polls
D+14.2
CANTOR
D+27.3
Fundamentals
D+23.8
Experts
D+20.4
Lite
D+21.5
Classic
D+22.3
Deluxe
<0.1
<0.1
Historical adjustment
Key
More weight
Less
We've collected 11 polls for Minnesota's regular 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 | Klobuchar | Newberger | margin | likely voter | Time-line | House effects | Adjusted margin | |
Nov 2-4 11/2-4 | Change Research | 953 | LV | 1.44 | 55% | 40% | D+15.0 | — | <0.1 | 0.6 | D+14.4 |
Nov 1-3 11/1-3 | Research Co. | 450 | RV | 1.02 | 53% | 33% | D+20.0 | 0.2 | <0.1 | 0.5 | D+20.3 |
Oct 29-31 10/29-31 | SurveyUSA | 600 | LV | 1.70 | 57% | 34% | D+23.0 | — | <0.1 | 0.1 | D+22.9 |
Oct 15-17 10/15-17 | Mason-Dixon Polling & Research, Inc. | 800 | LV | 0.77 | 56% | 33% | D+23.0 | — | <0.1 | 0.3 | D+23.3 |
Oct 12-13 10/12-13 | Change Research | 1,413 | LV | 0.23 | 50% | 41% | D+9.0 | — | <0.1 | 0.6 | D+8.4 |
Sep 30-Oct 4 9/30-10/4 | Marist College | 637 | LV | 0.36 | 62% | 33% | D+29.0 | — | <0.1 | 0.5 | D+28.5 |
Sep 10-12 9/10-12 | Mason-Dixon Polling & Research, Inc. | 800 | LV | 0.02 | 60% | 30% | D+30.0 | — | 0.1 | 0.3 | D+30.2 |
Sep 6-8 9/6-8 | SurveyUSA | 574 | LV | 0.01 | 53% | 38% | D+15.0 | — | 0.1 | 0.1 | D+14.8 |
Aug 17-20 8/17-20 | Suffolk University | 500 | LV | 0.03 | 54% | 34% | D+20.0 | — | 0.3 | 0.3 | D+19.9 |
Aug 8-11 8/8-11 | Emerson College | 500 | LV | 0.02 | 50% | 26% | D+24.3 | — | 0.5 | 0.6 | D+25.4 |
Jun 24-25 6/24-25 | BK Strategies R | 1,574 | LV | 0.00 | 57% | 37% | D+20.0 | — | 0.8 | 1.9 | D+22.6 |
Key
A = adults
RV = Registered voters
V = voters
LV = likely voters
= partisan poll
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. | ||
---|---|---|---|
Minnesota (special) | 100 | D+8.5 | |
Wisconsin | 78 | D+12.2 | |
Iowa | 75 | — | |
Michigan | 73 | D+10.7 | |
Ohio | 61 | D+11.9 | |
Pennsylvania | 61 | D+11.7 | |
Illinois | 56 | — | |
Colorado | 56 | — | |
Nebraska | 55 | R+15.5 | |
Kansas | 55 | — |
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+23.4 | D+24.0 | |
Inside Elections | D+23.4 | D+24.3 | |
Sabato's Crystal Ball | D+23.4 | D+23.0 | |
Average | D+23.4 | D+23.8 |
Nate Silver explains the methodology behind our 2018 midterm forecasts. Read more …
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