John Ellis thinks so:

Once Labor Day has passed, there will be five debates, in quick succession, on the GOP presidential candidates' calendars.  These will be important tests for Perry.  If at the end of two or three, it's clear that he's every bit the equal of Mitt Romney on matters of policy and politics, then the Perry juggernaut becomes all but unstoppable.  Romney's "I'm the only electable one" argument will vanish and the party's base will nominate one of their own.  If Perry stumbles badly in the debates, Romney's campaign gets a second wind.
Knowing that the only things standing between Perry and the GOP nomination are a couple of "good enough" debate performances, the GOP "establishment" faces a choice: they can cross their fingers and hope for the best or mount a sustained negative campaign to destroy Perry with the party's base.  It is likely that, after Labor Day, a sustained negative campaign against Perry will be launched. 
The sewage flood-gates have already opened, to some degree. For the past few months, Washington bureau chiefs of major news organizations have been inundated with rumors of Perry's alleged personal indiscretions and peccadilloes. And virtually every major news organization has some kind of "investigative team" looking into allegations of "pay to play" and other forms of corruption.  If all that that amounts to are some negative articles in The Washington Post and The New York Times, Perry won't be harmed.  It will take something serious, something big and proven to bring him down.

I agree. Perry isn't a lock, but something has to happen to take him down, or he will win. Political pundits have been dismissing Perry's lead by claiming that early polls "mean nothing." But when you examine this view closely, it turns out to mean "early polls meant nothing in the 2007-2008 cycle." In general, early polls mean a great deal in Republican primaries. They're not perfect, but they are strong indicators.

Obviously, you can't be certain about anything, and you have to make human judgments about the field. Does a candidate's lead represent a name recognition bubble that's likely to pop once voters learn more about the candidate's history or platform? (Think Joe Lieberman 2004.) When I look at the GOP field, I see an incredibly vulnerable Mitt Romney just waiting for someone to point out all the ways he's flouting the party's most deeply held beliefs, and  see Rick Perry as both the man to do it and a a perfect embodiment of the party id.

Another, more prosaic advantage for Perry is the distribution of the voters' support:

Rick Perry: 32 (18)
Mitt Romney: 18 (23)
Michele Bachmann: 12 (9)
Newt Gingrich: 7 (8)
Ron Paul: 6 (14)
Herman Cain: 3 (5)
Gary Johnson: 2 (n/a)
Jon Huntsman: 1 (5)
Rick Santorum: 1 (2)
Thad McCotter: 1 (n/a)

Ask yourself, which of Perry or Romney has the best chance to eat into the support of candidates currently supporting neither? The practically-nonexistent Jon Huntsman vote is sure to go to Romney. Maybe he can pick up the lion's share of the Gary Johnson vote. But the Bachmann and Gingrich votes, and probably, to a lesser extent, the Ron Paul vote, is all far better suited to Perry than to Romney. You can't assume that all voters are picking their candidates ideologically, but there is surely an ideological component at work. If and when the field gets narrowed to a Perry-Romney race, Perry will be in a commanding position to increase his share. Unless something knocks him off.