There are 435 individual House races and 35 individual Senate races up for grabs tonight. Using internal models as well as live returns, we'll be forecasting how likely it is that each party will control the House and Senate. We'll also be keeping an eye on key individual gubernatorial and Senate races. As the polls close and votes are counted, we'll be providing forecasts. Once a race winner is clear, we'll move onto another race.

Harry Explains the Forecast
What is this?
We'll be forecasting control of both the House and Senate and some individual gubernatorial and Senate races throughout the evening. That is, we won't just be telling you where a race currently stands. We'll be telling you where we think it will end up. These forecasts will be updated constantly throughout the evening as the votes are counted.
Methodology
These forecasts are made with the guidance of internal models. Each race will have a designation of a tossup, leaning towards a party or likely to be won by that party. Tossup means that the race is neck-and-neck, and there is no favorite. Leaning means one party is favored, though it is far from guaranteed that party wins. Likely means the party favored is a strong favorite. Even with a likely designation, we expect some races in which a party is likely to be won by one side to end up being won by the either side.
More questions?
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