Tonight the five Democratic mayoral hopefuls are set to square off against each other in a 90-minute debate at American University starting at 7:30 p.m. But unlike past debates, we can bet three of the candidates won’t be on top of their game.

While the majority of the city lay peacefully in bed last night, candidates Linda Cropp, Adrian Fenty, and Vincent Orange were hashing it out over the stadium lease, whose final vote came after midnight. Needless to say, they probably didn’t get a lot of sleep. If you see any of the three frantically demanding coffee from their aides before they hit the stage, now you know why. And if you see Michael Brown and Marie Johns — the non-council candidates — running around with mugs of Sleepytime Tea, you’ll also know why.

We’ll be there to cover the event, which promises to be interesting. The stadium issue is off the table and an ambitious school modernization bill just passed. So what the heck else are they going to talk about? Affordable housing, education, and general development issues are bound to come up, as are the usual claims of experience, character, and values. This may be the first debate where the candidates really try to differentiate themselves from each other, because if not, well, then they’re just a bunch of Democrats.

Fenty and Cropp are still the perceived front-runners and big fundraisers, but we expect that Brown and Johns will use their status as the campaign’s underdogs to relentlessly attack their performance on the council. Orange will, well, since he spent $12,000 on the sign outside his Chinatown campaign headquarters, we have no idea what he’ll do, but it’s sure to be big.