There are still some disputes over balloting procedures right now in Ohio, Pennsylvania, and Florida. Of the three, the exit polls from Pennsylvania suggest this will be a comfortable win for Kerry. (The exit polls for Kerry suggest a two-point lead in both Ohio and Florida, which, if it held up, would be beyond the margin of litigation, it appears).
Given how things are shaping up elsewhere, we can likely reduce the possibility of post-election litigation delaying the result of the election to Ohio and Florida. But even if there remain questions about how to call one of those states, it still appears quite possible that the race could be called in the Electoral College for Kerry. See Will Saletan’s analysis of what it would take at this point for a Bush victory.