Remember the Fox News debate in Orlando three weeks ago? Rick Perry took the stage as the frontrunner, Mitt Romney looked relaxed in spite of Perry’s presence and Herman Cain stood outside the inner circle. Since then, Perry fell in the polls, Romney reassumed his frontrunner status and Cain established himself as a genuine contender, thanks to several second-place finishes in major polls. Plus, the shadows of Chris Christie and Sarah Palin finally disappeared. Tonight, all eyes will be on Cain, who’ll occupy the podium between the two politicians who constitute his main rivals.

Expect Cain to do well. He has always been an eloquent and entertaining debater — and his success in the polls seems unlikely to go to his head in a performance-altering way. Because he doesn’t take himself too seriously, he strikes me as the sort of candidate who might actually enjoy a little verbal sparring if the other candidates decide to criticize him more vocally than they have at past debates.

Perry’s wife has promised he’ll do better in this debate than in the last one — and the economic focus should play to his strengths. But Perry has to do more than merely maintain his energy through the entire two hours and answer questions with coherent thought (with Perry, easier said than done!). He has to prove he’s likable.

Romney has, perhaps, the most difficult of jobs to do. He has to maintain the polished and professional appearance he has so carefully cultivated in the course of his presidential campaigns and has to display a Beltway outsider’s energy and zeal for free market solutions. Against Cain, he has to highlight his experience and perceived electability. Against Perry, he has to highlight his private business background. But he has to do both without seeming schizophrenic — and Romney has never exactly been known for consistency. That the debate is in New Hampshire should help, though. And, as with Perry, it should also help that the evening will be dedicated solely to economic issues.

Bachmann, having once performed well and having never really performed poorly (even if her fixation on Gardasil did make her appear outside of even the GOP mainstream), appears to be permanently ejected from the top tier less because of her debate performances than because of her Iowa-centric campaign and lack of relevant experience (as opposed to her lack of a legislative record, which I’ll continue to defend!). Even if she performs well tonight, she won’t overtake the frontrunners, as long as they also perform solidly.

Newt Gingrich will perform admirably, as always (and hopefully finally receive some credit for it); Ron Paul will be a relative delight in an economics-only forum; Rick Santorum will lack the opportunity to hit the issues he addresses best; and Huntsman will pretend he’s polling better than he is. Strategists say tonight is especially important for Huntsman and, yes, he’s made New Hampshire the linchpin of his campaign, but, even if he proves himself to be an alternate Romney … actual Romney is in the race. It’s been an uphill battle from the very beginning for him and GOP voters just won’t forgive that bipartisan background.

Romney will take the night — and the rest will just aim to hold on to what gains they’ve made.