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  • Key Races
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Political Parties

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Predictions of the 2018 election results

Senate Race
See a forecast where you live
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Most Likely Outcome
is forecasted to swing
Less likely election result
More likely
Margin of error predicts outcome 95% of the time

Forecast Map

Forecast just for Senate races on the ballot in 2018

Each race is shaded by who is favored (blue for Democrat, purple for independent and red for Republican) with an arrow indicating how much that side is favored. An arrow pointing to the left or right means a candidate is heavily favored while an upward arrow means a very close race.

Forecast full Senate makeup after 2018 elections

Each state has two halves, one for each senator who represents the state. The arrow tells you how Democratic or Republican the state is expected to be based on an average of the forecast win margin (for seats up this year) and the overall state partisanship for other seats.

Harry Explains the Forecast
What is the margin of error?
Look, we’re making a forecast. It’s not going to be perfect. Anything within this range could reasonably happen, though we expect the result to be close to our best estimate.
How does the prediction update?
The prediction updates every day as more polls come out. The prediction should become more accurate the closer we are to the election.
More questions?
Tweet at Harry @forecasterenten
Harry's Races to Watch
The 15 races with the smallest margin between parties
Predictions Scorecard
Circles are drawn to mark each prediction made since The Forecast started. The timeline below shows a detailed history of the estimates.
Estimated seat advantage over time
By Harry Enten, Sam Petulla, Parker Quinn, Brice Acree, Vijith Assar, Matthew Conlen, Brad Oyler, Will Mullery, Joyce Tseng and Mark Barilla.