Does Texas Governor and Republican presidential candidate Rick Perry prepare for the debates? He clearly does, he just can't quite carry it off. His signature moment of the night came when he teed up what was supposed to be a devastating indictment of Mitt Romney's flip-flops and get lost somewhere in the middle and barely made it out the other side.

Perry has been coming back to Earth lately, partly on the basis of his uneven debate performances. Orlando didn't do anything to change that dynamic--indeed may have accelerated it.

The Texas governor had a handful of notably bad answers. He had a very compelling reply to Michele Bachmann's suggestion that his HPV vaccine mandate was a gift to the drugmaker Merck. Perry replied that he had been lobbied on the issue by a young woman who eventually died of cervical cancer.

During the debate it seemed an instance of Perry thinking through and practicing an answer to defuse a line of criticism. But journalists pointed out on Twitter immediately afterwards that, according to published reports, Perry didn't become acquainted with the woman until after his decision.

On immigration, pushed onto the defense for the second straight debate, Perry said you don't have "a heart" if you don't support his policy of giving the children of illegals in Texas in-state tuition. Conservatives hate being called nasty people, especially by their own, and Perry will spend a long time living this answer down.

On foreign policy, he was asked a tough question on how he'd handle loose nukes in Pakistan and replied with loosely connected bits from briefings on Asia that didn't come close to answering the question.

In the first two debates, Perry stood out for his sheer stage presence even if his answers weren't always crisp or deep. Thursday night, he faded more into the line-up of the other candidates at the same time he wasn't any better on the substance. His weak performance will stoke more speculation about New Jersey Republican Gov. Chris Christie possibly entering the race.

Romney has weathered Perry much better than anyone would have expected. By pushing the Texas governor on his more adventurous positions in his book "Fed Up," especially on Social Security, he's kept him in an awkward spot. Sometimes, Perry sounds like he's adopting the standard Republican position that the program merely needs to be reformed over time; at other times, he says he's sticking by his contention in the book that the program is an unconstitutional failure and perhaps should be devolved to the states.

It's become clear that Romney has an advantage over Perry in these forums simply because he's more articulate, detailed and authoritative-sounding in his answers; he's like a boxer with a reach advantage.

Of course Romney has vulnerabilities--his aforementioned flip-flops, his Massachusetts health care program--but no one has been able to fully exploit them and Romney has some kind of ready answer for every challenge. It really helps to have been at this five years rather than five weeks.

Romney also benefits from the current dynamic in the race: Since Perry is ahead in the polls, the lesser candidates tend to aim all their barbs at the Texan rather than him.

Among those second-tier candidates, Rick Santorum, Newt Gingrich, and Herman Cain all had good nights--especially Santorum who got a lot of airtime and has been consistently strong in the debates. Michele Bachmann didn't have much of an impact at all.

But, as has been the case since he shook up the field with his entry a month ago, the story was Rick Perry. A few weeks ago, the question was how far and fast he would ascend; now, after his third debate, it's how much he'll drop.

Rich Lowry is editor of The National Review and a syndicated columnist. He is a Fox News contributor.