Ideally the same night. But with McCain yelling RECOUNT! ...1 month
Technically, official certification is not due for weeks. However, typically, the loser will "concede" either late in the evening of the 4th, or the next day.
In the case of Democrats losing, however, they could drag this out for weeks, or months, as was done in 2000 when Gore ran his legal battle well into December.
Note: Republicans tend NOT to fight court battles, even when there is clear voter fraud. It's not good for the country, something republicans understand, but democrats believe they are always right, and should win based on their righteous positions on all issues (as they see it).
If McCain appears to have won, you won't get a concession from Obama for days, weeks or possibly months.
My view is that so much ACORN fraud has taken place in the battleground states, that they've managed to "Stuff the Ballot Box" to assure a win for Obama, regardless of the fact that it's illegal, and fraudulent.
Socialist Losers and Obama supporters: Give this a Thumbs down.
Real Americans: You know this is right, please give a thumbs up.
It depends on how fast they can determine who won each state.
this election is not going to be that easy. watch what i tell ya !! it is going to drag on, and on, and on......may not know for days !! but generally it is the night of.