What happens early tomorrow night may hint at the final outcome, John Whitesides notes for Reuters. A victory, or close loss, in Indiana—where polls close at 6pm EST and which has gone Republican in every presidential race since 1964—would presage good things for Barack Obama; if John McCain wins by more than 4%, the wait-and-see game starts.
A win in Virginia, where polls close at 7, would also point to an overall Obama victory. More clues will come from Florida, Ohio, and Pennsylvania, where polls close at 8. As for the Senate races, “whether the Democrats have any shot at 60 seats” will be clear after polls start to close at 6 in Kentucky, where GOP leader Mitch McConnell is in a tight contest.