If you'd like a summary of what to watch for tonight, see this excellent hour-by-hour election guide.
Here's where we'll be updating results on 270toWin tonight:
President: As states are called, they'll appear in the table in the bottom half of the page. The electoral vote count will change, along with an updated probability of victory for Clinton and Trump and other stats. The electoral map on the top half of the page will also fill in.
We'll also be updating a map in the iPad App. Go to The Library > 2016 Projections. The first map there is the Election Night Map. Tap the Refresh button to see the latest state results.
Senate: Democrats need to gain 4 (if Clinton wins) or 5 to take control. The map will fill in as states are called; use the Forecast button to see expectations for the uncalled races. The table to the right will summarize the results, making it easier to see who is on track to control the Senate. Any party gains will be displayed in the table under the map.
House: Same concept as the Senate map; Democrats need to gain 30 seats to take control. The table below the map shows the most competitive races; click any state to see all the results for that state.
Governor: Only 12 gubernatorial elections this year; we'll fill in the map as those results are known.
The home page interactive electoral map will not be updated tonight. It remains available for you to create and share your own forecasts. For those looking for the Road to 270 combinations calculator, it is now available as a standalone version. There's also a related calculator for tie combinations.
Finally, here's a list of poll closing times. This is a guide for when results will begin to be reported by the media, not when your particular polling place may be open.