Michele Bachmann, in that first category, so far has been unable to capitalize on her Iowa straw poll victory and breakout New Hampshire debate performance. Jon Huntsman, meanwhile, is scraping bottom in polls despite heightened media attention and solid credentials, including two years as ambassador to China and a job creation record as Utah governor that rivals Perry's in Texas. And let's not forget Ron Paul (hear that, Paul fans out there?). He cemented his standing as light years outside the mainstream by calling repeatedly for the abolition of the Federal Emergency Management Agency—before, during, and after Hurricane Irene.

Bachmann had a summer surge in Iowa, leading in four polls until Perry showed up and vaulted to the top. She is trailing both Perry and Romney in Iowa, South Carolina, and Florida, states where she is spending most of her time, and she's down to 4 percent nationally in a new Fox News poll.

There's no more clarifying indicator of a candidate's standing than media scrutiny, painful as it can be. Bachmann's fade from “serious” to “iffy” came into focus recently when The Washington Post op-ed page featured no less than three full-blown appraisals of Perry's ideas. “Bachmann has always been an emotional choice,” says GOP strategist Jim Dyke. “That's difficult to sustain. When people start looking at experience and policy and winnability, she starts to have a hard time.”

In some ways this trajectory was foretold months ago, when some conservatives pointed out Bachmann's lack of executive experience. Hot Air blogger Ed Morrissey, for instance, suggested back in March that Bachmann, a member of the House, run for the Senate instead of the White House. “We can expect to see executive competence become a big issue, and the Republican nominee will have to possess a track record for accomplishment in that context,” he wrote.

The belated arrival of Perry offers GOP voters a jobs-oriented governor who also radiates the visceral, religious-tinged conservative appeal that has been so potent for Bachmann. As Public Policy Polling's Tom Jensen observed in an analysis of shifting sentiment among South Carolina Republicans, “Perry seems to be filling a void for voters looking for someone more conservative than Romney and more credible than Bachmann.”

If Bachmann epitomizes the politics of passion, Huntsman is plagued at times by what you might call a dynamism gap. It's not his only problem by a long shot, and there's no question he connects with some people in certain situations. But there is what Dyke delicately calls a “less than exciting” quality to many of his appearances, which worries likely supporters such as Bob Gibbs, owner of a yoga studio in Salem, N.H.

Gibbs attended a Huntsman town meeting and told me he very much likes what he hears from the candidate on economics, education, and foreign policy. Gibbs then added, unprovoked, that Huntsman isn't being aggressive enough. “He needs to tick it up. I don't think he's presenting an image to other people that he's really forceful and a take-charge kind of guy. He's got to have more of a presence, show a little more emotion,” Gibbs said. In a follow-up email, he said he isn't sure if Huntsman has “it”—which he described as “a certain charisma that draws you to the person.”

Huntsman has never scored higher than 4 percent in a national poll and topped out at 6 percent two months ago in New Hampshire, where he is staking his bid, before falling back to 3 percent. That's even after a heavy round of media exposure centered on his belief in evolution and man-made climate change, heretical in today's GOP, and critiques of his rivals as extreme, a strategy bound to alienate many Republicans.

Many on the right, including The Wall Street Journal editorial board, are lauding Huntsman for his new conservative-on-steroids economic plan that would repeal the Affordable Care Act (aka “Obamacare”) and the Dodd-Frank financial regulation act; rein in the Environmental Protection Agency and the National Labor Relations Board; slash corporate and personal tax rates; end the mortgage deduction and other tax loopholes; and eliminate the alternative minimum tax, the earned income tax credit, and all taxes on dividends and capital gains. But Romney and President Obama are putting out economic plans next week and Perry is making his debut in a debate. The spotlight will move on.

The only real questions that remain about the GOP field are whether Palin will run and, if she does, whether she'll have any impact. Dyke is among those expecting a campaign. “Nobody's gonna have a party without me, dammit,” he said, channeling a Palin thought balloon. He adds that she's an energizing force for the GOP but won't get very far without donors or a grassroots structure

“She'll constantly be in a cloudy, dusty brawl with—quote—the establishment, whether that's the media or Republicans,” Dyke said. “She'll be like the person shot out of the cannon under the big top. Everyone looks up and watches them fly across the big top and they safely land in the net and then we move on.”

Which brings us back to Romney vs. Perry, and Romney's new status as No. 2 in national polls. He's getting advice across the political spectrum on how to fight the Perry threat. Former Bill Clinton adviser William Galston, confessing terror if Perry somehow goes all the way, suggests that Romney's theme be “Rick Perry wants to repeal the 20th century. I don't. And neither do the American people.” Republican Marc Thiessen says Romney plans to bide his time waiting for Perry to implode or be destroyed—but wonders if that's too risky. Texas Monthly published tips from 11 people who have run against Perry in the past. “Just be ready for a fight, 'cause you're going to get one,” counsels Democrat Marvin Gregory, who lost to Perry in a 1994 race for Texas agriculture commissioner.

So far Romney's engagement has been limited to swatting at the idea that “career politicians” (translation: Perry) can drag the country out of recession. It's going to take a lot more than that to derail him. Democrat John Sharp, who lost a 1998 lieutenant governor's race to Perry in part because of a flood, described him to Texas Monthly as a relentless campaigner with intense focus, sharp advisers, and extra help from above. “Running against Perry is like running against God,” Sharp said. “Everything breaks his way!”