It’s a close one, folks, and it could get ugly.

That’s the state of the presidential election, according to Rick Hasen, the law school professor behind Election Law Blog and author of The Voting Wars: From Florida 2000 to the Next Election Meltdown, published last summer by Yale University Press.

Hasen, of the University of California, Irvine School of Law, talked to The National Law Journal the day before the big vote about the consequences of a squeaker election between Barack Obama and Mitt Romney.

Here’s what he had to say. His answers have been edited for clarity and brevity

The National Law Journal: What’s your prediction about how close the race will be?

Rick Hasen: There’s no question that the outcome of the election in a popular vote will be close. It’s not clear that the electoral vote will be as close. For that to be close, it’ll have to be in a state whose electoral college votes are crucial to the outcome of the election, like Ohio, Florida, the usual suspects. We have a particular worry in Ohio in terms of finality. We’re expecting a whole bunch of provisional ballots — at least more than 100,000 there. Those votes won’t even start to be counted until November 17.

NLJ: Explain provisional ballots, please.

Hasen: Those aren’t absentee ballots. Those are ballots with some question, like voting at a place different from where the voter is registered, where the voter was lacking identification or voting at a poll with extended hours.

NLJ: And those votes won’t be counted until November 17?

Hasen: They won’t even be opened until November 17.

NLJ: What’s so bad about a delay? So what if it takes a few days to figure it all out?

Hasen: If the delay is because the election is extremely close, it could turn on the results of absentee and provisional votes. Each party will be looking for ways to get an advantage. You can imagine a situation in which there’s a dispute over how to count classes of provisional ballots in Ohio — like if they’re cast in wrong place. You’ve had some rulings in the federal courts but not in the [U.S.] Supreme Court. It could be a nightmare.

NLJ: Have we learned any lessons from the Bush-Gore 2000 election?

Hasen: One thing that’s different is the rise in social media, especially Twitter. It’s an important part of the political conversation. Social media makes people less politically tolerant. At the same time, there’s less confidence in our election process. There could be protests.

NLJ: What’s wrong with protests? Some people would say that the American public was too ambivalent about the Bush-Gore outcome. Isn’t protesting a good thing?

Hasen: Protests and riots in the streets after an election? I don’t think that would be good.

Contact Leigh Jones at ljones@alm.com.