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Chance the Democrat wins (99.6%)
Chance the Republican wins (0.4%)
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.
We've collected two polls for the Washington 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.
|margin||likely voter||Time-line||House effects||Adjusted margin|
|Public Policy Polling||675||LV|
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.|
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.
|Cook Political Report||D+23.9||D+24.6|
|Sabato's Crystal Ball||D+23.9||D+23.5|
Nate Silver explains the methodology behind our 2018 midterm forecasts. Read more …